Have you ever owned a console that wasn't from Nintendo/Sega/Sony/MS (and if so, what was it and how was it?)

[SanAndreasX]

An Atari 130XE. It was technically a computer, but it played the best games to be found in the 1980s outside of the NES, and it also would have been cross-compatible with the 5200 if not for the fact that it had a cartridge slot far too small to accept a 5200 cartridge.