DrDJ Free is a little applications for DJ wannabes. It can play any audio file QuickTime can play and allows you to crossfade between songs. You're in control of the transition, but DrDJ Free can do everything automatically, too. The on-the-fly playlist can contain an infinite number of songs (depending on how much RAM your computer has), so you can fill it up and let DrDJ Free handle everything.
Mac OS X 10.0 Server
||Mac OS X