PandaBar

PandaBar is an excellent Pandora client for Mac. It runs on the menubar and you won't even know it is there unless you need to change the station.

Pandora is an Internet automated music recommendation service that can play songs by your favorite singers and bands. All you need to do is tell the application what artists you want to listen to, and it will automatically find and play new songs continuously. PandaBar requires you to sign in with your Pandora account when you first launch it, and it will automatically start playing music when you sign in. You can control music playback by clicking on the menubar icon or by using one of the many keyboard shortcuts available. You can use the default media playback keys on your keyboard as well.

Although PandaBar can use Growl for notifications, this feature is only available on Mountain Lion and you need to have Growl installed, too. The notifications pop up when a song starts playing and they include a name of the song and its artist.

You can thumb up and thumb down songs from the menubar to rate the songs that you like the most. This information will be transferred to your Pandora account automatically.

In short, PandaBar is a great tool for anyone who just wants to listen to music and not have to worry about changing stations. It is ideal because you don't need to have a browser tab open just to listen to your favorite songs.