Sci-fi Yuri Anime and Manga

I decided to catalogue all of the titles I could think of that scratch the itch for science fiction as well as yuri. I came up with more than I expected. Maybe I'll do a fantasy-themed list later. If you have suggestions for additional titles, feel free to chime in with them!

In anime:

Battle Athletes OVA (6 episodes):
In the distant future, the most prestigious athletic event is the annual interplanetary Cosmo Beauty competition, which determines the strongest athlete. Akari's deceased mother Tomoe became the greatest Cosmo Beauty in history, and Akari strives to win the Cosmo Beauty title for herself. Akari and her teammate Kris fall in love. They are separated at the end- because of Kris' duties as a priestess and Akari's duties as the new Cosmo Beauty- but promise to reunite.

Battle Athletes Victory (26 episodes):
A goofier, more wtf-inducing version of the OVA story. The first half takes place when Akari competes on Earth to qualify to enter the Cosmo Beauty competition. BAV also goes beyond the OVA's timeline by revealing a very...unexpected reason for why the Cosmo Beauty competition was created. Thankfully, Kris is still present. Her attraction to Akari is more overt in the TV series than in the OVA, but the attraction on Akari's side is more toned down. A comedic love triangle dynamic forms after Ichino, Akari's childhood friend, meets Kris. In the end, Ichino and Kris are still competing for Akari.
Here are my two reviews of this series.

Blue Drop (13 episodes):
Girl meets alien. Unfortunately, the alien is from a much larger (all-female) race that plans to colonize the Earth. The star-crossed lovers in this series don't get a Happily-Ever-After, but it was nice to watch them while it lasted.
My review.

Fight! Iczer-One (3 episodes):
A crappy, ultra-violent 80's OVA. If you like that sort of thing and you like yuri, you'll love Fight! Iczer One. I only watched one episode in high school. An alien race known as the Cthulu (with members who have names like Big Gold and Sir Violet) invades Earth. A female android named Iczer-1, who the Cthulu created, saves a human girl named Nagisa after the Cthulu kill her classmates and parents. I think there was some yuri (or hinted yuri) between them? I remember that two alien women were making out in the first minute or so of the OVA. According to Wikipedia, Nagisa and Iczer-1 survive and the world is reset to how it was before the Cthulu invaded, with Nagisa not remembering Iczer-1.

Kashimashi (12 episodes + 1 OVA):
In the first episode, our protagonist Hazumu gets killed by an alien spaceship and regenerated as female instead of male. Cue love triangle involving the girl who rejected Hazumu pre-spaceship crash (for the stupidest reason possible) and Hazumu's childhood friend. Two of the aliens start living with Hazumu so they can observe human behavior and provide comic relief.

Kyoukai Senjou no Horizon (one 13 episode season + another on the way):
In a futuristic recreation of Japan's Sengoku era, a high school boy named Toori rallies his friends (including a cute lesbian couple, seen above) to help him save the girl he loves from...I don't want to explain it all again.
Here are my two early impressions and my write-up on it in my Anime of Interest to Yuri Fans in 2011 list- and here's my final review.

Mahou Shoujo Lyrical Nanoha (13 episode first season + 13 episode second season + 26 episode third season):
Starts out as a straight-up (and unfortunately, boring) magical girl fantasy, but between the cloning and the Time and Space Administration Bureau, it becomes more of a sci-fi/fantasy hybrid.  Once you get past...well, most of the first season, it really is worth watching.
Reviews here, here and here.

Mai-Otome (26 episodes + one 4 episode OVA + one 3 episode OVA):
Another title I haven't watched since high school. Mai-Otome, you are not, really, a very good series, but I had a lot of fun watching you, and you drove me to collect a million GB of slash fan art. This spin-off of Mai-Hime takes place in a future Earth, in which the military might of nations depends on women who gain super-abilities from nanomachines they choose to be implanted with. There are several yuri characters and multiple pairings.

Mouretsu Pirates (airing now):
Went a little overboard with the screencaps. ^_^; So, Marika is now captain of the the Bentenmaru. The story is still awesome and there was some nice Marika x Chiaki subtext in the most recent episode. (Still looking forward to seeing Lynn and Jenny as a canon couple later also.) If you aren't watching this series, you really should give it a shot.
Earlier impressions here and here.

Project ICE OVA (3 episodes):
Tried one terrible episode in high school. I remember the plot being something about a post-apocalyptic future in which all men have been wiped out.

Re: Cutey Honey OVA (3 episodes):
Android meets police chief in a cracktastic, Gainax-animated version of Tokyo. I love this OVA. It's my favorite part of the Cutey Honey franchise. Technically, just about every installment in the Cutey Honey franchise could go on this list, but I'll just list this OVA since it's the most yurilicious one. Here's my review of the original Cutey Honey manga, which is definitely worth reading.

Senhime Zesshou Symphogear (airing now):
Three of the four leads sing to transform into super-powered battle armor that they use to kill aliens called Noise. Two of the leads and one of the villains are confirmed yuri characters, but none of them are interested in each other. This show hasn't impressed me, but there's half a season left. We'll see what happens.
Earlier impressions here and here.

Simoun:
In the world of Simoun, everyone is born female. Some countries use surgery to allow people to become male if they choose, but in the country of Simulacrum, each person can choose their gender at a sacred spring. Simulacrum is at war with Argentum, a nation that want the technology Simulacrum uses to propel its flying vessels known as Simoun. The Simoun are piloted by priestesses called Sybillae, who can't choose a gender without being disqualified from being Sybillae. Of course, several couples form, and the lead couple is a yuri one through the end.
An excellent series.

Stellvia:
I still haven't watched this. I've hear that it's good, and have had it on my to watch list for a long time. It's a space opera with a likeable-sounding lesbian side couple. (Update: Hmm, doesn't sound like there's all that much yuri, even from that one couple. I shall adjust my expectations accordingly when I watch the series.)

The Third:
In the distant future, 80% of the Earth's population has been wiped out. A group of beings known as the Third (because of the red third eye on their forehead, which they use to communicate with each other) monitor the humans to "protect" them from using too much technology. (Any human caught using forbidden technology is killed.) Honoka is a human who was born with a blue third eye. It grants her special abilities, although not the same ones used by the Third. She travels around in a tank doing odd jobs for different people. A supporting female character has a crush on her. Thanks to P.S. for pointing this series out!

To Aru Kagaku no Railgun (26 episodes + 1 OVA episode):
In Academy City, which is technologically 30 years ahead of the rest of Japan, the government develops the abilities of children and teenagers who are psychic. A series with this concept could easily be A) trite or B) creepy and Orwellian, but it's mostly a fun romp with a group of friends who solve different incidents involving rogue pychics. One of the major characters is a yuri character, who has a crush on the lead.
Here's my final review.

Yokohama Kaidashi Kikou (two 2 episode OVAs):
In a post-apocalyptic world, as the human population dwindles down while peacefully living in the twilight of its era, an android named Alpha runs a cafe while waiting for the cafe's owner to return. In the second set of OVAs, Alpha goes on a trip to explore the world beyond what she's seen. Another android, Kokone, is in love with Alpha.
If you have the chance at all, try Yokohama Kaidashi Kikou. Here's my review.

In manga:

Battle Athletes Daiundokai (4 volumes):
I haven't read the Battle Athletes manga yet, but it sounds awesome. It only covers the Cosmo Beauty competition (what the OVA covers) and pairs Akari and Kris more overtly (and focuses on them more) than either the OVA or the TV series do. As in the TV series, Akari and Kris kiss after Akari wins the Cosmo Beauty title, but Kris doesn't say that she did it because of something or other having to do with her religion. (I call BS on that explanation anyway. Almost from the moment they met, Kris was all over Akari in the TV series. I like to think that she gave that excuse to calm the flustered spectators while secretly thinking, "Oh my god oh my god, I finally did iiiiit!") As in the OVA, Akari and Kris are separated after Akari wins the Cosmo Beauty title. Unlike in the OVA, Akari reunites with Kris, and then Happily-Ever-After. (It sounds like the manga pairs Lahrri and Mylandah more overtly too.) Additionally, Akari is less of a crybaby and more competent in the manga. AUGH, I want to read this series.
Update: Teaser scans from the manga!

Blue Drop (1 volume):
While the Blue Drop anime is a prequel to the invasion of the Arume, the Blue Drop manga shows the Earth after the Arume have colonized it. The Blue Drop manga is a collection of one-shots featuring a few different couples, all but one of them yuri. The anime has the luxury of more time to develop its characters and their relationships, but the manga is ultimately happier. (Overall, I like the anime more.) The closest thing the Blue Drop manga has to a lead is Yui, a half-Arume half-human lesbian who kicks ass. (I liked Mari plenty, but wish the anime had revealed what happened to her after the invasion.) I haven't read any of the other Blue Drop one-shot collections because they're supposedly horrible.

Chirality (4 volumes):
I'm embarrassed to admit that I haven't read this yet. It's one of the earliest English-language yuri manga releases. In a post-apocalyptic world in which the men have not been wiped out, a girl named Shiori and an android named Carol fall in love and save the world.

Girl's Only's "Endless Narcissus" (one-shot):
Part of a collection of one-shots that ran in Carmilla, a now-defunct lesbian magazine. "Endless Narcissus"'s lead is so...well, narcissistic, that she has a clone of herself created for sex. (She killed her former girlfriend for cheating.) The clone kills her after she sleeps with someone else. I know, wtf.

Himitsu's Shoujo's "Planet Aimer-Lis" (one-shot):
Chi-Ran's work really doesn't do it for some people, but I enjoy her yuri work. "Planet Aimer-Lis" is a cute one-shot about a girl named Yuma who meets an alien named Aimée from an all female planet called Femme. Aimée came to Terre (Earth) to find a bride (as women from Femme can only have children with women from Terre), and proposes to Yuma. Silly but fun.

Iono-sama Fanatics (two volumes):
Iono-sama doesn't have much sci-fi, but what it has at the end is noteworthy. Iono is the charismatic lesbian queen of a small country who comes to Japan to find sobame. (Sobame can mean "lady-in-waiting" or "concubine.") Iono's battle cloak counts as sci-fi, but what's really noteworthy to me (and most yuri fans) is the way two of Iono's sobame have a baby together at the end.
My review.

Kashimashi (5 volumes; 2 omnibi in print in the English release):
Same premise as the anime, but with a better ending.

Kaguyahime (27 volumes; re-printed as 14):
Before entering foster care, Akira lived in an orphanage on an island in which children were beheaded in sacrifice to Kaguyahime after turning sixteen. After Akira and some of the other orphans found out what was happening, they escaped the island. Years later, they learn that nobody who escaped the island has made it beyond their sixteenth birthday without dying violently. Akira, now fifteen, and some of the other orphans return to the island to figure out if there's anything they can do to escape that fate. Cloning plays a major role, and Akira's foster sister Mayu, who loves Akira, comes to the island as a stowaway. Pretty fascinating stuff so far.

Phryne magazine issue 1's "Salyune" (one-shot):
A cute but unremarkable one-shot about a woman who confesses her love to a woman who is on the same spaceship full of female refugees traveling from a devastated Earth to the planet they plan to settle in.

Pure Marionation (re-printed as 3 volumes; originally 2):
An android girl named Anon is allowed to attend high school. There, she falls in love with a girl named Aina. How will Aina react when Anon comes out as an android? This series starts off dull, but becomes a cute, surprisingly sincere love story by the end. I especially liked how Anon and Aina got together in the final chapter and thought it was charming that Anon's coming out is about her being an android instead of her being in love with a girl.

Rakuen le Paradis volume 3's "A Lifeform in Puberty - Vega" (one-shot):
A fun, slightly futuristic one-shot by Hayashiya Shizuru, about an alien who needs a kiss from the human girl she loves to get her full abilities back so she can fight alien monsters.

Renai Idenshii XX (1 volume so far, still running):
Another series about a post-apocalyptic world in which men have been wiped out. The twist is that the women have been divided into Adams (those who adopt a traditionally masculine role) and Eves (those who adopt a traditionally feminine role). It is forbidden for an Adam to have feelings for another Adam or for an Eve to have feelings for another Eve. Our lead, Aoi, is an Adam who falls for another Adam named Sakura. This series has some well-written characters, and I know that the point is how stupid the system that Sakura and Aoi live in is. (And by extension, how stupid patriarchy, gender discrimination and heteronormativity in general are.) But the "post-apocalyptic world composed entirely (or almost entirely) of women" scenario needs to be put to rest.
My review of volume 1.

Simoun (1 volume):
A Yuri Hime manga version of the Simoun anime (another, much worse manga version ran in Megami) that only ran long enough to promote the anime.

Stellvia (2 volumes):
It has more yuri than its anime counterpart. Thanks to A Day Without Me for letting me know about it!

To Aru Kagaku no Railgun (7 volumes, still running):
Covers the same territory as the first half of the anime, then continues beyond it. I still like the anime and plan on buying it when Funimation releases it (whenever they get around to it), but have lost interest in the manga.
Reviews here, here, here, and here.

Transistor ni Venus (7 volumes):
A female spy named Enus travels the galaxy to carry out missions, having flings and relationships with different women along the way. Basically Star Trek meets James Bond, but with a yuri spin. Strangely, what I read of this series didn't do much for me. Other people have really liked it, though.
My review of volume 1.

Twinkle Saber Nova (3 volumes so far; seems to be on hiatus):
In the distant future, a cheerful, spacey girl named Hayana attends a school that lets students form any club they want. Hayana uses super-powered battle armor to fight her school's World Domination Club. A girl who fights alongside Hayana has a crush on her.
Twinkle Saber Nova is Fujieda Miyabi's least interesting series, but it isn't bad.
Here's my review of volume 1.

Yokohama Kaidashi Kikou (re-printed as 10 volumes; originally 14):
Read this if you haven't. It's a masterpiece. The ending isn't explicitly yuri, but it is definitely yuri-friendly. As a yuri fan and a fan of good stories, I loved it. Won't spoil it, though.