I once did a slideshow of game console-to-computer upgrades, and the APF Imagination Machine figured prominently in the list. That's because it was a combination of the APF-M1000 home video game system and the "IM-1," which was a large keyboard/speaker dock with a built-in cassette tape player (for program storage and retrieval).
What an odd machine. To my knowledge, the M1000 was the only video game system based on the Motorola 6800 CPU, which is one of the grand-daddies in the microprocessor world (first released in 1974).
While neither the console nor the computer fared well commercially, this distinctive advertisement leaves a positive impression. It was brilliantly playful and colorful for a computer ad of the time (1979; this particular scan of the ad comes from 1980).
Discussion Topic of the Week: Best console add-on of all time?