Experimental quantum communication complexity
  We prove that the fidelity of two exemplary communication complexity protocols, allowing for an N-1 bit communication, can be exponentially improved by N-1 (unentangled) qubit communication. Taking into account, for a fair comparison, all inefficiencies of state-of-the-art set-up, the experimental implementation outperforms the best classical protocol, making it the candidate for multi-party quantum communication applications. 
Pavel Trojek, Christian Schmid, Mohamed Bourennane, Caslav Brukner,   Marek Zukowski, Harald Weinfurter