In the 80's, Bandai tormented the world with the "Gobots", their take on the "transforming robot" craze that never captured the imagination like Transformers did. Maybe they would have had better luck pimping these transformable NES cartridges instead.
Released in the 80's by the Japanese toy company, these "Kasetto Sentai" (Cartridge Corps) figures were small replicas of actual Famicom (the Japanese NES) cartridges, which were able to transform into the characters of the games they were representing. So the Mario cart became Mario, and the Gradius one became a freakin' Vic Viper. So great.
Below you'll see how these figures compared in size to the actual Famicom cart, along with the full range, which also included Bowser, Ghost 'N Goblins and Dig Dug.
Kasetto Sentai [Video Game Den, via Fuck Yeah Famicom]