[jonjon10002]

Picked up one of these as a kid at a garage sale for a buck, mostly to take it apart and see how it worked. Internally, it was a board with maybe a dozen daughter boards, each a vertically-mounted, removable card. All transister-diode logic. The game "cartridges" were just cards with different jumper wires inside them that physically rewired the system.

In addition to the overlays, it came with dice, money, poker chips, and some other board game components you used in conjunction with the video game itself. I'm guessing everyone promptly lost all of this, which would make a complete system even more rare.

Magnavox didn't sell many of these, but made their real money patenting everything and then suing Atari and anyone else making a video game system attaching to a TV.