One of my first video game systems, after my Intellivision, was the Atari 5200, the horribly mutated big brother of the 2600.
Between the 2600 & 7800 was the worst Atari system ever made, but with better graphics than the 2600. To give an idea of how bad, the Atari 7800 was backwards compatible with the 2600, but not the 5200! Talk about killing the upgrade path.
Some of the not-so-memorable games were Jungle Hunt, Centipede, Joust, Buck Rogers: Planet of Zoom, and my favourite, Congo Bongo. And if you got sick of the 15 games made for the system, you could get the VCS cartridge adapter to play 2600 games - for only $15 more than an Atari 2600.
Here's a positive(ly funny) review on the worst system ever made.
Here's a link to the emulator if you want to bring your computer down to the level of a 5200.
Or just buy the thing on e-Bay for $4.99, and pay $200 for shipping the 200 lb bohemith.
This auction is for a Atari 5200 game console only. It appears to be in good shape it does show wear and scratches from use. I was not able to test it so I am selling it "as is". The game Frogger is in the console but it has no original tag and someone just wrote with masking tape "frogger" so I am not positive if that is the game for sure.
Be sure you're running it on a separate circuit breaker. Buy lots of extra joysticks. On second hand, for $4.99 you'll probably get a cardboard box with a hand-drawn Atari logo on it and a Tupperware lid with frogger-labelled masking tape, so don't bother.