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The Atari XE Game System (XEGS), a consolized version of the Atari 400/800/XL/XE computers. However, it could be expanded into a computer with the full function of an Atari XE computer, with keyboard and disk drive. The Atari 8-bit line in itself shared its basic architecture with the Atari 5200, to the point where many 5200 games were ported to the Atari 8-bit computer, either officially or by hackers. Plus, it took standard Atari joysticks instead of the crude analogue stick that the 5200 was stuck with, and Genesis controllers would work with it because the Genesis has the same 9-pin connector for its controllers as Atari.
This video isn't the XEGS per se, it's the Atari 400 Mini, but it can be configued to any configuration of the Atari 8-bit, which includes XEGS and 5200 ROMs. One of my favorite A8 games was Donkey Kong, which was the most failthful home port of Donkey Kong released at the time. It was more faithful than Nintendo's official NES version.
