Pokemon Stadium

Pokemon Stadium is a special N64 game available now in Japan. Pokemon Stadium allows two players to port their Pokemon from their Gameboy game Paks, via a special Controller Pak, onto their N64 game Pak. Once ported, the Pokemon are transformed into dazzling 3-D polygonal beasts of war!

However, the only thing it is good for is two player battles. There is no central adventure game like the Gameboy game. All you can do is fight in a full 3-D arena with another player. That's it. But it seems to be fine with Japan's Pokemon players, because the game is doing great. Depending on Pokemon's success in the states, we could see it over here soon, but no date has been set.