QUOTE(discoleo @ Sep 19 2006, 00:27)

Is there any program around that would allow me to play an mp3 file using a different speed (i.e. slower or faster).
You can create interesting effects by changing the playing speed. Some DJs use such features.
Is it possible to implement in the ID3-Tag such a tag, specifying the playing speed, e.g. as frames/ second. I remember, that it was possible with vinyl plates to choose different playing speeds, too.
There are several programs and plugins for winamp and even foobar2000. for winamp, you can either use the included "signal processing studio" and load the "simple pitch and tempo controls" file to do so. More dedicated plugins are ds_pacemaker, or foo_repeat which might work for your specific needs.
Edit: more info in this other thread :
http://www.hydrogenaudio.org/forums/index....showtopic=45114