Peggle, which MSNBC named one of the "Top 5 most addictive computer games of all time," is a 2D game in which the goal is to use an aimable ball launcher at the top of the screen to fire a ball into a screen full of pegs and bricks and eliminate all orange-colored pegs and bricks before running out of balls.
The iPhone version of the game has seen rave reviews and has made converts out of many doubters. For only $0.99, it's definitely a steal. The only real complaint from the iPhone version was the lack of music, but we've heard that music is on the way.
App Store Link: Peggle, $0.99 (Until June 14th)