Custom-made Home Theatre
What can I say about this? It's ridiculously cool. Short of having a bowling alley in my basement, this is about as awesome an accessory your house can have. Well, a hot tub, too.... but I digress. There are a lot of ways this can fit into even a small house, as well. Is your garage one big storage shed? Turn it into a home theatre. This company sells predesigned theatre setups, wall units, soundproofing equipment... basically everything you can think of. Check 'em out.