Planescape Torment - updated graphics and a similar epic-yet-personal storyline would be awesome. Maybe I could run into a grown up version of that alley I saw born in the original. All grown up to be a street now.
X-wing/TIE-Fighter - Seriously, a stream of crappy SW games over the last decade, but no sequel to these gems?
Republic Commando - What happened to Sev?! Tell me you bastards! It was the first time I actually liked my squadmates in such a game! I want more!
Dungeon Keeper - Hell yeah
Beyond Good and Evil - Any game where you get a camera (thank you Bioshock) I go nuts and take pictures of everything. Much love.
Evil Genius and Republic - The makers (Elixir Entertainment iirc) went down the tube, so no can do I'm afraid. Still, I loved both.
Startopia - Sold only 10.000 units, which is ridiculous because it's the closest to Dungeon Keeper as you can get and it's hilarious.