I don't have anything really outrageous, but I was a big JRPG fan during the SNES and PS1 years. I never had a Sega CD and only got a Saturn after I got my dreamcast, and I've never paid more than new price for any games, but a few did go up in price. I've also picked up a few things recently in Japan that are going for quite a bit more in the states.
Suikoden 2
Shining Force 3 US
Albert Odyssey
Dragon Force
The Zelda bonus discs for GC
Metroid Prime Collection
Tech Romancer
Radiant Historia
Pikmin 2 (just found out its rare in this thread, too bad I got it used without a box)
Fire Emblem PoR
Pepsiman PS1
Mother 3
Umihara Kawase DS
and a few other's I'm sure. Not really sure what else I have of value, since I haven't considered selling any games in years. I only sold off games I didn't like, with the sad exception of some DC games I wish I had not sold, particularly Hyper Magnetic Neo and power stone. Actually, I sold almost all of my DC games to pay for Metal Gear Solid 2 while I wasn't working, but I think that was the last time I sold any games.