Star Blades, made by my pal and GM Inquisitor Thaken. Weird features include very minimal use of guns, but still a lot of interstellar combat (all of which is boarding actions) and very extensive political rules:
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Lungfish Alpha, just plain weird but thoughtful game about a future in which Manitis have colonized the galaxy. The yahoo group is pretty disused, but if you can get past theads for sexy biker chicks and viagra, it's worth it.
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Both of these, and many others, are available through darkshire, which is one of the best websites forfree rpgs
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Also, there is an old one that I can't remember, that I wish I could find. Somebody had taken all of the races from Cosmic Encounter (Philanthropist, Virus, Laser, Zombie, etc., all of which were on the level of Star Trek's Metrons or Organians, though definitely more sinister) and turned them into super-advanced alien races who battled for control of the galaxy using a minion race. And who were these minions? You guessed it: humanity.
Great fun for the darkly minded. I can't even remember the title, but I'd love to find a copy.