HEATTACK is a fun single person arcade style shooter game. The game supports Windows 95/98/NT/2000/XP and up. The entire game, including graphics and sounds, is licensed under the GPL. The game is fully payable, although there are a few things missing and left to be done. These include a way to die (the player presently lives forever), and the lack of a scoring system. You can download the game and the source code from here.