Snoop Dogg is holding out for a collaboration with either the Rolling Stones or Madonna - because he wants to experience what it's like not to be "the big one" on a track.
He tells Nylon Guys magazine, "I wanna be on a track where I'm not the big one. I wanna do a Madonna or a Rolling Stones or a Quincy Jones - something where their name is bigger than mine."

contactmusic, MadonnaTribe

(In a way, Madonna and Dogg already collaborated: in Arthur and the Invisibles movie)