Theres a few club nintendo games (they suck to play) that had limited releases in Japan only. I think a Game & Watch Collection and 2 with the guy from Zelda. Ruppes...? Names elude me atm. Stuff like this will actually be collectable in the futre. The games your going for will real only be as expensive as they are now. It's just most of the other games will be worthless. If your going, you're gonna have to dig alot deeper than Pokeman and Chrono Trigger. The really rare games usually end up the crapiest ones no one even wanted to buy. (Sound fun?) Or even noticed. Or the End of the line when everyones moved on. Not the popular games. They just hold there value.