RadioTuner – Listen to Any Radio Station via Dashboard
There are quite a few ways to listen to the radio on your Mac, through iTunes, Safari, various Dashboard widgets, but RadioTuner is probably the best way yet.
RadioTuner is a Dashboard widget that allows you to customize the list of radio stations, allowing you to hear what you want to hear rather than whatever is in a predefined list (like iTunes and many other widgets provide).
The interface is small and easy, simply paste the radio feed URL into the widget and save. The developer also has a growing list of searchable station feeds available, searchable here.