John Paul Jones joined Robyn Hitchcock on stage at the Hardly Strictly Bluegrass Festival in San Fransisco's Golden Gate Park to play the song Glass Hotel yesterday.
"Just imagine your listening to this out doors, on a sunny day in the park," Hitchcock told the crowd.
Watch at 1:45 to 1:55, where Hitchcock says something to Jones which makes Jones laugh and stop playing for a second.
The free festival takes place every year and features a number of acts. Hitchcock performed on the Porch Stage, which Jones also played on with Seasick Steve later in the day.
Last year Robert Plant and the Band of Joy opened the Banjo Stage on the Friday night of the festival. Plant also joined Patty Griffin during her set on the Saturday portion.
Update: Robert Plant also made an appearance at Hardly Strictly this year, joining both Buddy Miller and Patty Griffin during their sets. He sang a song he wrote with Patty during her set:
With Buddy Miller he joined Griffin and Emmylou Harris for Somewhere Trouble Don't Go, which Plant played harp on: