Actually the thought crossed my mind. It's the garage so aside from heat issues, it would be pretty simple I think. I am in Phoenix so the garage could easily get 120 plus degrees on some summer days. As some have so graciously suggested, I can't mount it to the ceiling because of a ceiling fan. Again, Phoenix, there's no way that fan is coming down. I also have a pretty nice 4 coat faux finish applied to the walls that took about a week to paint so I'm hesitant about carving that up.
It's a one story house so the ceiling is an option, but that attic gets pretty damn hot (did I mention I live in Phoenix
Right now I'm toying with the idea of building a oak box that could be stained to match the cove moulding along the ceiling and suspending it from the ceiling with some cables or pipe above the couch. Then run power into the box for an outlet that would power the projector and some low voltage lights mounted in the bottom of the box. Sort of a projector house - shelf - track lighting system all in one.
Sushi, don't worry about the duplicate suggestion, I'm grateful for the help.