UPDATE: Spotify has stopped supporting third party applications and they won’t be available in future versions of Spotify. They started to focus on their Web API.
This is one of the applications they developed using Echonest + Spotify , I would recommend using it instead of mine, since mine will not work anymore : SortYourMusic
Beatify is a Spotify application that shows beat per minuet (bpm) information for songs in a playlist. I’ve developed this application last year for personal use, but it wasn’t complete and I never had chance to publish.
It shows BPM for songs and allows you to Sort by BPM.
Spotify stopped app submissions for their market in March, 2013, but you can still use this application on your computer following instructions on Readme file.