Well, I can't really say I've done anything *that* crazy...
I know I talked to myself a lot while playing Wing Commander 1... which is odd, since it didn't have the vocal taunts of the later games to get me fired up. Still, there were instances when I'd be fighting with the arrow keys, completely engrossed, talking to the Kilrathi fighter that would always be *just* out of my sights. After one episode, Dad sat me down and we had a long talk about, well, talking to yourself! I think he thought I was losing my mind...
I've also bought not one, not two, but three separate computers, just to make sure I always had access to Wing Commander 3. I went through a G3 iMac, iBook, and lastly, a lowly PowerBook, all in the name of finding a machine that could run WC 3 just right. That might not sound *too* crazy, but considering that I've bought all of those computers over the past 3 years, just to play one game... well, I certainly think it was odd, looking back.
I know I'm missing something -- I'll write if I can remember it.