Have you ever wanted to create your own atari games from scratch? Thanks to the Grand Idea Studio, you can download the files to make your own cartridge PCBs. There isn’t a ton of information here, as this is an old project that isn’t being supported anymore. However, you can download the instructions, schematics, and gerber files for carts that work in the 3 main models of the atari 2600. As [Tyler] over at Adafruit points out, you could easily 3d print your own shell as well.

http://hackaday.com/2012/06/16/build...ri-cartridges/