Go to this thread for today's game, which is a squad based first person shooter, that requires a lot of strategy to win, called Hidden & Dangerous Deluxe.
It's around 260Mb in size, which for an FPS game is quite small. however considering this, the graphics are surprisingly good; though not as good as the games released over the last few years:
http://www.giveawayoftheday.com/forums/topic/3856#post-41732