So amazon just announced the Amazon Fire TV USB stick.
http://www.amazon.com/gp/product/B00...ANPVVG3JOPO2KK
For the next 2 days it will be $19 for Prime members. I have no idea how good this will be, but for less than $20, you would be stupid not to take a chance on it. I would think it should let you install XBMC. Even if not, it would let you stream easily to it.
I bought one for myself and one for my Brother In Law.