FloJuggler: Track periods of one or more girls. Seriously. The site's FAQ if you're wondering why you'd want to use such a service.
Grabarz & Partner's website looks oddly familiar... A German ad agency, apparently they couldn't be bothered of thinking of something original so they ripped off an existing concept.
Needs. More. Cowbell. Morecowbell takes any MP3 file and adds synchronized cowbell along with random Christopher Walken clips. For example, David Bowie or Coldplay.