It would be cool to get a riff for Phish`s "Wadding in the Velvet Sea" which is a very good song, check it out.

dont have the sheet music for it but its G D Em C D and the bridge is Bm C Bm C Bm C Am Em and then back to G D Em C D

A few additions on the bridge

The song is:
G D Em C D repeated

Then the Bridge is
Bm C C9 Bm C C9 Bm C D Am C D G

The C9 is really quick, its actually just a matter of hitting a D instead of a C on the fourth beat of the measure.

Then it goes back to
G D Em C D for the solo and the rest of the song.

At least thats how I have always played it.