One of the most addictive Linux games, Frozen Bubble, just got updated to version 2.0.0. The new version brings you a new single player game mode (multi player training), network (LAN, Internet) game mode (up to 5 players), fully revamped graphics, full joystick support, recording and playback of all games with non-predefined levels and more.
This was one of the first games I played on Linux (On a Knoppix live CD), and I still love it!
-Stephen