Hey,
I’ve always wanted to a real DJ application in Flash, and now with player 10’s new sound API we’re getting closer! Here’s a little app I’ve been working on;
No mp3s are part of the file itself, it runs off the users own local mp3 files. The pitch, volume and position can all be played with at runtime. I know it doesnt look much at the moment but I want to get most of the functionality done before starting to skin it.
It’s all OOP based so extending the ‘Player’ class into ‘Turntable’ or ‘CDJ’ would be easy. I also have a basic ‘Mixer’ class that Players get added to and hopefully will get to work on it some more to have crossfaders, effects and loops ect. I’m aware of a few bugs, like sometimes the track starts again after its finished and sometimes doesn’t.
For those of you that have used software like Virtual DJ etc should be able to use it to some degree.
P.S. press the ‘power’ while a track is playing, its pretty kool 
EDIT, This requires Flash Player 10 to work
http://idontdance.co.uk/lab/flashdj/FlashDJ.swf
lewi-p