Found this last night and thought it was worth a mention. Its one of the most touted game Ive ever seen. PC Gamer gave it the "Best of All Time" award this year. Ive never played it and it doesnt look like anything too special but everybody seems to rave about it so I figured for $2.50 ya cant really lose.
If you havent played it, it might be worth picking up especially for this price.