Their pre-Fergie early releases were jazz-tinged and knotty, but The Black Eyed Peas' shift toward party-minded hip-pop led to big-name collabs in the ‘00s. The collective assisted Brazilian legend Sergio Mendes on his 2006 update of the samba smash “Mas Que Nada”; Peas leader will.i.am acted as pop whisperer for the likes of Britney Spears and Flo Rida, and he invited Justin Bieber on board for his electrifying solo track “#thatPOWER.”