Jimmy Page joins Donovan on stage @ Royal Albert Hall, London June 03 2011

(C) Photograph by Virgilio Fino/Govinda Gallery

Jimmy Page made a surprise appearance with Donovan @ Royal Albert Hall on Friday June 03.
He played on "Sunshine Superman" (Here on video) at the beginning of the show then at the end he came back onstage and they played the song again with Jimmy on guitar.
He stayed to play " Mellow Yellow"( click for video with Jimmy):

"Sunshine Superman"

Full article on this gig with Pics @ Tight but Loose

Another article with Pic on Rolling Stone US