Disney's Aladdin Plot Generator
Need I say more?

Prophesy Generator
If you're short on something for your local Yoda to babble at the hero, this should work for you. It might also inspire a plot.

The Random Plot Generator
Sometimes it makes sense... sometimes it doesn't.

Random Plot Generator for Bob and George
100% nuttiness!

Random Plot Generator for Bob and George Mark 2
Based off a different script, this one's a bit more sophistocated.

The Sims 2 Plot Generator
Again, extreme nuttiness.