Komi is a 2D arcade style game licensed under the GNU GPL. The basic aim is to collect all the money by extending Komi the Space Frog’s tongue, while avoiding the bad guys. Komi’s spiritual predecessor is an old Spectrum game called Glug Glug which had similar(ish) gameplay.

http://dl.openhandhelds.org/cgi-bin/pandora.cgi?0,0,0,0,27,434