Coop

"The 6507 chip is quite similar to the 6502. The 6502, as you might recall, was used in everything from the Nintendo 8-bit, to the Apple II, to the Commodore 64, to the Atari 400/800 line, to the Atomic Bomb, and even, in an altered form, to the Turbo Graphix-16. Yes, that chip got around, alright."
- How to turn your Atari 2600 into a portable one.