Airfoil allows you to send any audio to AirPort Express units, Apple TVs, and even other Macs and PCs, all in sync! It's your audio - everywhere. With Airfoil you can take audio from any application and send to your AirPort Express units, as well as Apple TVs, and even other Macs and PCs running Airfoil Speakers! Transmit audio from RealPlayer, Windows Media Player, QuickTime Player, and other media players. Send audio from web-based applications like Pandora, Last.fm, and other to the AirPort Express. You can even stream audio from audio devices like RadioSHARK, XM and Sirius radios, around your house.

Requirements: Intel, Mac OS X 10.6 or later.

Airfoil 4.6.2
Released on 10/21/11
* Airfoil now properly captures audio from apps created with Fluid.
* Airfoil's volume slider behavior has been improved, with new artwork and enhanced feedback via artwork.
* Airfoil now disconnects from remote speakers upon sleeping, to prevent error messages on waking.
* An issue where Airfoil could not launch an app because of quarantine, even though quarantine is disabled, has been corrected.
* The unnecessary Interface Settings preferences have been removed.