Mike's Amazing Cakes (previously) of Redmond, WA made this detailed, wildly improbable Batcave cake for a client, complete with a cake Adam-West-era Batmobile.
This Batcave has the Batcomputer, the Batmobile, an atomic reactor, and many other devices. If you look carefully at the side of the Batcave, you will see the Batpoles. It looks like an elevator shaft with two long poles in it. The Batpoles lead up to Wayne Manor. Compressed steam caused a platform at the bottom of the Batpoles to go back up to Wayne Manor. Half way down the Batpoles is an Instant Costume-Change Lever so Batman and Robin change into costume as they come into the Batcave.
On the other side of the Batcave is the secret entrance. It is in front of the Batmobile. This Batcave is an edible set designed for the client's die cast Batmobile. The Batmobile is sitting on the giant turn-table of the Batcave. It rotated the car so it would be facing the secret entrance to the Batcave and be ready for when Batman and Robin needed it.
(via Mitch Wagner)