I was referred to this website by a friend and think it's the coolest thing going.
Right now I'm using it to design a mug that custom fits my wood-burning stove but has flutes on the side to allow the heat to escape and also has a longer folding handle that will double as a detachable spork.

heheh. it's addictive folks.

http://emachineshop.com/

I've seen the site also. Please let us know how the finished product turns out.:)