If you feel restricted with Last.fm's "scrobbling" capabilities, Firefox add-on Harmony will help you get more music onto your charts. Harmony lets you share tracks played through Pandora and other FoxyTunes-compatible players on your Last.fm profile. Foxy-tunes is another Firefox add-on; it's a music player that controls iTunes, Windows Media Player, and 21 other music jukeboxes from your browser status bar.
After downloading Harmony, a small "audioscrobbling" icon (a curvy "AS," which will be familiar if you use Last.fm) appears in the bottom-right-hand corner of your Web browser status bar. To start using the add-on, click the icon and enter your Last.fm account information into Preferences. Select "Connect to Last.fm" to make sure your music gets scrobbled.
When you are ready to jam, go to Pandora.com and start a radio station. Harmony will automatically pull up information about the band you are listening to. A band picture, list of similar artists, and a biography linked to the band's Last.fm page will all show up in the Harmony box. While you are listening to your tunes, Harmony is scrobbling them all to your Last.fm profile. The add-on will also scrobble songs when you use FoxyTunes.
However, Harmony doesn't always perform its scrobbling duties. At times, this add-on is puzzlingly unresponsive and unpredictable; there is no way to be sure that your music will be scrobbled. When it is not working, the Harmony box will say nothing but "Connected to Last.fm," or an error message will appear. The error message will tell you that an error concerning "BADSESSION" has occurred. Note that you may need to restart your browser to begin using Harmony for its scrobbling features.
If you are meticulous about your Last.fm charts, Harmony is a good tool for you--just don't expect it to always work.
Now if there was only a way to scrobble tunes from your car.
Disclosure: Last.fm is a part of CBS Interactive, which also publishes CNET Downloads.