Well, I'm not as extreme as I'd like to be, but I do walk around everywhere using the gollum and Pippin voices I've learned to do so well. I also quote like, the whole book. And, if I see non-fans, I usually turn my back on them, unless thier my best friend or something. I'd definately get mad if someone insulted LotR, though, definately.
The thing I'd like to do is: Go to all of the cast members' houses, get a bunch of costumes, maybe the ring, and walk around every day in those costumes for the rest of my life (or at least until they fall apart or something
).