Realplayer. One of my classes (History of Jazz) requires us to use it to listen to some of the pieces... I try to find as many of the pieces as I can on P2P services so I dont have to use it, but some of the really old ones are impossible to find so I dont have a choice
At least it is almost time to reformat anyways, so there wont be any problem getting rid of it when I am done with the class.