Sighted at Warner Bros. studio lot: a golf cart styled as a pudgy version of the Tumbler, the urban tank Batman used to navigate Gotham City in Batman Begins and The Dark Knight. Apparently the golf cart was the creation of a crazed fan working at the studio—not Christopher Nolan as first reported—who equipped the small vehicle with speakers to simulate the growl of the "real" Tumbler's engines.
The baby Tumbler even has a mock jet engine at the back! As a golf cart designed to go around the studio however, the baby Tumbler doesn't have any storage space for golf clubs and the like. Also, since it doesn't appear in the movie, we doubt if it will suffer critical damage and pop out its own Batpod any time soon.
No word on who did the custom work, or if it's available for paying customers. How much would you spend on something like this, if you had cash to burn?