What amazing game did you play when you were a younger that none of your friends had or knew about?

For me it was Team Buddies for the Playstation. For so long I thought this game didn't exist because I'd never talked to anyone who had played it, or even heard of it. I had also forgotten the name of the game up until recently so I couldn't google it.

But anyway, I played that game to death, and I seemed to be the only person I knew who ever played it or even heard about it.

So what are your games that only you knew about?