And this one seems pretty perfect for your situation. I highly recommend it. It's base is a bit off-par though, so I might recommend getting an additional subwoofer.
http://www.sybarites.org/2007/05/23/steinway-lyngdorf/
My roommate, and I have a 1080p projector and PS3, with a 105in screen. We need help finding a speaker system. doesn't need to be fancy, 5.1 will do fine. And it would be nice if it wasn't too expensive. Thanks...

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