Check this. My wife used to work in Children's animation. They wanted to do an animation of the "HOLLYWOOD" sign on the mountain, and the people that own it require 10K just to use it.
10 fucking grand just to use AN ANIMATED VERSION of it.
It costs 25K to use the Final Jeapordy theme song, and the happy birthday song is even owned.
http://www.unhappybirthday.com/ Time Warner will sue your ASS if you use it in a movie without permission.