A few nights ago while procrastinating a few more hours I came across a man named Oystein Baadsvik. He is a professional tuba soloist, and has a very interesting repertoire, including his own piece, Fnugg.
http://youtube.com/watch?v=mHMyrhilkdo
Interesting use of multiphonics and other sounds that you don't normally hear brass instruments make.
Now excuse me while I lock myself in my room to practice it...