Deputy Dog has a list of 10 Stunning Ultra-Geeky Home Cinemas. Being a geek myself, I fully intend to build me one of those as soon as I can afford it -- though I probably won't go as far as these people have. Mine will based on the bridge of the Enterprise D, of course -- a bit like #5 on the list -- but it'll be a lot simpler and a lot more practical. Something like this, maybe:
Check back with me in about five years and I'll let you know how it turned out :)