The Potion Factory's Tangerine! 1.0 for Mac OS X lets users create playlists by analysing the tempo and beat intensity of music.

The software aims to help users assemble playlists for specific moods or needs — for exercise or travel, for example. It will load and save playlists to iTunes, fetch album art from iTunes and export Beat Per Minute (BPM) information into iTunes.

Andy Kim, the co-founder of Potion Factory, had this to say: “Music is an important part of lives, and certain kinds of music can help us perform different tasks much better. Tangerine! will save a lot of time for people because they won’t have to manually hunt down those songs anymore.”

Potion Factory claims that on a Core Duo iMac, Tangerine! can analyse 3,000 songs in 20 minutes, but the application cannot analyse songs purchased from the iTunes Music Store, because the digital rights management (DRM) system applied to those songs limits fair use.

Tangerine! costs $24.95. A 15-day demo is available.