I had some ideas, but some don't seem practical, so here's a few that seem ok:
Build it in a game-chair
Make it modular (separate pieces)
Make a carved Acrylic case (see-thru)
Make a vaccu-form case (exact size of components, except processor and heatsink. Needs to breath.)
Build it like a tower-fan (tall and skinny)
Build it in an old ammo case
Looking for other awesome ideas. Throw them at me.
EDIT: I am completely competent in building computers. Not asking what parts to build it with, asking for EPIC case ideas and such.