Pyrcast for Mac is a simple, clutter-free Pandora app
Pyrcast lets you listen to stations from your existing Pandora account and features station management, song history, album artwork, and configurable global keyboard shortcuts. It also lets you rate songs, as well as receive Growl notifications for each song that plays. The latest version has also brought a number of bug fixes, a redesigned UI, volume controls, improved audio playback, and the app now remembers your login details so you don't have to enter them each time you start it.
The drop-down Menubar icon that normally lets you control your stations has been taken out of version 2.0 due to some bugs, but the developer promises that it will be back in the next update.
Pyrcast requires a free Pandora account (only available to those in the US) to work, and it runs on Mac OS X 10.6 or newer. Pyrcast costs $4.99. You can get it from the Mac App Store.