The Zombie Car (a.k.a. The Freakmobile) was used by the mutants in Treehouse of Horror VIII's "The HΩmega Man". It also appears in The Simpsons: Hit and Run.
The HΩmega Man[]
Mayor Quimby generates a great deal of controversy over a "frog's legs" joke he makes about France, and when it becomes obvious that no apology is forthcoming, the French president launches a neutron bomb directly into Springfield. Homer had been inspecting a bomb shelter he was considering buying from Herman and after the blast, Homer emerges from the shelter to find that he seems to be the only person to have survived.
He misses his family, but he quickly gets over his loss and dances naked in church. While dancing, he is confronted by a band of Springfield citizens who have become mutants. They claim that they want to create a perfect world in which the mistakes of the past will be eliminated. This, of course, includes killing Homer. Homer flees in a hearse (while being chased by the mutants in a zombie car) and arrives at his home where he finds that his family survived the blast because their house was protected by so many layers of lead paint. Seeing Homer reunited with his family, the mutants see the error of their ways. They hope they can build a Utopian society with the Simpsons, but Marge and the children open fire with shotguns that they were hiding behind their backs. Homer and his family decide to take advantage of the nuclear holocaust and go and steal some Ferraris.
The Simpsons: Hit & Run[]
The Zombie Car reappeared in the game's final level. Homer, at the advice of Comic Book Guy, managed to take a Zombie Car to pursue a long, black, car-shaped probe for the Alien mothership to the Nuclear Power Plant. According to Comic Book Guy, it ran on human brains.