Let's see here...in college I switched it up every year.
This Means War- Busta Rhymes and Black Sabbath
I Want It All-Queen
The Game-Drowning Pool (I used it before Brad Lidge stole it for his own)
Back in the Saddle-Aerosmith (used this past year after I came back from surgery)
Some of my other personal fav's that I've seen used before- Real American (Hulk Hogan's entrance song), The Gladiator theme, Karate Kid theme (You're the Best Around), O Fortuna, and the Fraggle Rock theme.