Yes is definitely in my top 5 (and I remember when their first album came out!). My band used to play a couple Yes numbers, including Yours Is No Disgrace. Also in the top 5 is Led Zeppelin (we also played a lot of their stuff) and Creedence Clearwater Revival.
My favorite, though, is Emerson, Lake and Palmer. It's hard to pick one piece of theirs as my favorite song -- maybe Tarkus or Pirates.
My favorite modern artist is David Benoit (he has written and played a lot of the music for the Peanuts movies, etc. in the last 10 years or so), and favorite group would be either Spyro Gyra or Russ Freeman and the Rippingtons.
As for someone current that most of you have actually heard of

, I guess it would be Blues Traveler.
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Jim