Oysterhead is a really cool newer rock band, I believe (I can not find very much information about them) formed in late 1999.

What makes them so cool is Trey Anastasio (Phish) on guitar, Les Claypool (Primus) on bass and Stewart Copeland (I don't know what band he's from) on drums.

The band is definately a cross between Phish and Primus. Trey does a great job following along to Les' basslines, and they take turns singing. If you like Primus or Phish, definately Napster an MP3 or two (But make sure to delete it after 24 hours!)