I thought this would be a great idea while out running this morning, and thought someone must have done it, but I've not had much luck finding what I'm looking for.

Does anyone have any links or ideas, I've listen to a few on you-tube and they are lame IMHO, I don't want countdowns or anything like that, just 20 seconds of kick ass propper heavy fast music followed by 10 seconds of chilled. Something like this when it starts getting fast(which came on while I was sprinting on Sunday and was most awsome.

Dropping to something sedate like the intro to this (my idea of sedate is probably not the same as everyone elses)

It's probably not hard to do if you have the right programme and arn't a techno numpty (grok hit magic noise box with sick to free little men in-side singing)