This is a really worthwhile video to check out. It isn’t on YouTube or Google Video, so I can’t embed it here, but follow the link. This guy plays a chord sequence from “Don’t Stop Believin'” by the band Journey and sings about 20 different popular tunes over it. It shows you how much similarity there is in rock and pop song chord structure.
I especially like how there is some guy in the room playing video games through the whole video. If you’d like to hear the original Journey tune, here it is: