Rogue Amoeba has released Airfoil 3.1, the latest version of its Airport Express streaming audio utility for Mac OS X. Airfoil allows users to send audio from any application to an Airport Express, and can also send audio to multiple Airport Express units simultaneously. New features in version 3.1 include support for the Apple TV’s new AirTunes feature, which allows Airfoil to stream audio to the set-top box, and support for Airfoil Speakers for Windows. The release also fixes a DVD playback issue with Mac OS X 10.5.2, and includes various other fixes and improvements. Airfoil 3.1 requires Mac OS X 10.4 or later and sells for $25; users of Airfoil 2 can upgrade for $10. In addition to the Mac version, Rogue Amoeba also offers Airfoil 2.5 for Windows; it sells for $25 as well.