I've gone and entered myself in a cake contest put together by
http://www.threadless.com/. You can view my entry at
http://www.threadcakes.com/entries/view/278#0. I decided to also post the pics here so you can sorta see the process of making a 3-D cake. Here we go:

Here is how it starts. Every cake is made from scratch.

Baking. This is exciting, isn't it?

Uh, Jeff? Cleanup time, babe.

They started as blocks.

Starting to take shape.

Here I'm about half-way through. Each dude was made to order.

Voila! "The Last Piece" is born. That little sushi on the board is about the size of a Tic-Tac.

As you can see, one dude is wearing a shirt. No, he isn't cold, that is another contest shirt. It's a bunch of sushi taking revenge on their chef.

The rules stated we had to photograph us eating the cake. Here is the big chop. Notice the meat cleaver.

YUM!
There you go. I'm not giving away all my secrets because there aren't any but at least you have an idea of the process.