Got a spare $9,500US to spend?
How about a lifesize cast replica of a T.rex skull? (linky)
Or if you are looking for something a bit more subtle, for $5,750 you can get a half skull suitable for hanging on the wall of your lounge (linky) (spokesmodel not included).
If those are just a bit too cool, how about an arm or a leg?
If I had that sort of disposable dosh I'd think about it, just because I like the idea. "Oh yeah, I've got a Tyrannosaur skull in my lounge"....
$100,000 will get you a whole skeleton, although that probably won't fit in the lounge.
Budget wise though, I might just have to settle for a tooth. Albeit, a pretty big one. It would go nicely with the fossil Great Shark tooth I have already.