The Java 4K Game Programming Contest challenges developers to create online games with one ridiculous, artificial constraint: the game logic, the graphics, the music, the sound effects, etc. must collectively fit within a 4,096 byte jar file! Click on one of the thumbnail images below to play one of my entries to J4K2012. You may need to adjust the browser zoom to avoid an empty region around the game applets.
Feel free to hack up the source code of the title applet above.