On Episode 13 of Cloud Cover onChannel 9, Ryan Dunn and Steve Marx showed a fun Windows Azure application that takes any song and turns it into a swing time version of the song. Here's an excerpt of Steve's blog post about it:
I've put together a sample application at http://swingify.cloudapp.net that lets you upload a song as an MP3 and produces a "swing time" version of it. It's easier to explain by example, so here's the Tetris theme song as converted by Swingify.
Steve's blog post has plenty of examples of "swingified" songs, as well as all the technical details about this application, which makes use of Python in the cloud. Enjoy!