I'm looking for a change of pace for my tabletop gaming group; we've been playing D&D3.x for the last few years and the thrill of dragonslaying is starting to wear. I'm thinking that some hard science fiction would be a nice change.
So, I'm looking to find a decent system, hopefully backed up with a couple of sourcebooks but not requiring a massive investment in splatbooks and sourcebooks out the wazoo. I'm prepared to fork out, say, $100 max.
As a major criteria for the setting, I would like it to be completely free of magic (or the Force, or psionics in touch with the afterlife, or any of the other magic-cloaks that SF sometimes wears.) This time around, I just want gritty realism bundled with a playable system.