The Bonhamizer
Here's my Music Hack Day San Francisco hack: The Bonhamizer. This hack lets you hear what it would be like if John Bonham was in your favorite band.
It works pretty well on many songs, and not so well on others. I hope to smooth out the rough edges in the next few days. Here are some of my favorites:
The code for this hack is on github at github/echonest/bonhamizer