The MyCube is a computer made by Mapple.
Homer saw a MyCube in a Mapple Store and was eager to get one, even though he didn't know what it did other than look cool. Interestingly, no one working in the store seemed to know, either.
When Bart fled the Mapple Store after pranking Steve Mobbs' announcement, he tried to use a MyCube to help him escape ("MyCube, take me away!"), but all it did was play music.
The MyCube also glowed while being off.
Behind the laughter
The MyCube is a parody of the Power Mac G4 Cube, sold by Apple from 2000 to 2001.