Just a simple idea. I don't really intend to use it, so if anyone else wishes to personalize it and call it their own, I'm not gonna stop you...

You know, in your dreams, you can do whatever you want, right? Fly, kill, create, destroy. You can be your own god.

Well, the idea is that the main character can suck another person's soul into his dreams. From there, he goes into a semi-coma state where he can do whatever he wishes to the soul (in some kind of Yugioh-esque "shadow" world). In addition, he can just simply leave the soul trapped in his dreams forever.

Twists: sucking/killing his best friend (or trapping his best friend in his mind forever, and his best friend is well...stuck in his mind), sucking and trapping his worst enemy only to have that enemy try to take over his mind (at which point there can be this cool sequence where he's in the dream world battling himself), etc, etc.

Sound cool to anyone?

Yup. No point in letting them stay in your mind, right? Otherwise it'd be like a crappy rehash of Navi from Zelda 64. They'd be stuck in your head, going "Hey! Look! Listen!"

or "Hey! Die! Loser!"

Sounds like Psychonauts from DoubleFine.

Tim Schafer is a bad mammajamma.