Frozen Bubble is a free software Puzzle Bobble style computer game which is available on several operating systems including Linux, Windows, Mac OS X and the Symbian Series 60 line of smartphones. There is also a single player Java applet version.
The latest version 2.0 includes an adjusted launcher speed, new scoring system, 4 lives and online multiplayer mode, but only available to Linux users at the time of writing. Version 1.0 of the game is available across all platforms including Symbian Series 60 line of smartphones and a single player Java applet version. Written in Perl, the free to play Frozen Bubble features 100 levels and a cute penguin (I think it’s supposed to be Tux) who shoots to form bubbles of the same color.
More info here.