Of course you know that all of the Nikon flashes can do multi-flash. That P5000 shot posted above was taken with three flashes. Current line-up only the SB-900 and a SU-800 controller can be master. The recently superseded SB-800 can be a master too. They will work wirelessly or with wires.

While I have a SB-800, I am using mostly older non-i-TTL flashes with wires.