OK, well my budget is around a couple hundred dollars a month, depending on lots of other things, but my bills are relatively small at the moment.
As far as what I can get away with, nearly anything aside from major wall tearing construction projects (a bigger sub is a possibility, and probably needed)
For media servers, I have a hp desktop computer that was pretty powerful about 4 years ago when I bought it, so that is a possibility if I run some sort of front end, like frontrow, which I have on my macbook, and maybe a way to control it all from the couch.
I guess I should also give you all an idea of what I have at the moment. I have a 44 inch LCD projection by Zenith, a DVR from time warner cable, a PS2, x-box 360 (currently being repaired by Microsoft), a pretty good dvd player from samsung and the receiver is a yamaha rx-v663. The speakers arn't great, mismatched from give aways and pawnshops. I also have a Harmony h659 remote. (that I am wanting to unload for a better model for my DVR.)
Pictures of my new space will follow.