The VMU was a pretty cool piece of tech back in the day, born out of the Tamagotchi craze of the late 90's this is not only the source of memory for the Dreamcast but is also a portable gaming device

Because of the VMU, systems like the NINTENDO DS, handheld streaming media players, and other well known (if you look hard enough you can see the relevant technological advance) devices, all circulate around the idea of having an artificial memory in a sleek, handheld device with LCD screens.

This is a great device especially since you can put little games on it and go in the car or on the airplane and play them.