Rogue Amoeba Software today announced Slipstream, a new application that allows audio from any application to be heard through remote speakers attached to Apple’s AirPort Express. “AirTunes isn’t just for iTunes anymore–now users longing to listen to audio from RealPlayer, Windows Media Player, and any other application over their remote speakers will be able to do so, with Slipstream.” Slipstream will be available early next year for an introductory price of US$20.