I have this odd habit of learning TV openings/video game themes to shows I really like.

I've accidentally taught myself:

Donkey Kong background/opening music (don't ask!)
MXC Theme (Most Extreme Elimination Challenge)
Pink Panther Theme
Law & Order
Pressure Cooker (Atari 2600 music)
Space Battleship Yamato
The Inspector
The Rockford Files
The Munsters

These songs work well to open with when you come back from a break when playing live.