I've been a fan of Instinctiv for quite a while. As someone who mainly listens to music while doing something else (like coding), it's great to have a music player that doesn't require any maintenance beyond hitting "next song" every once in a while. Good complement to Pandora when you aren't feeling adventurous.
I think it's worth mentioning that the Android version of this player, although not as full-featured as many of the other alternatives, is also quite elegant.