Codemasters' new driving game DiRT, released for Sony PlayStation 3 this month, makes effective use of hybrid third-order Ambisonics via the console's eight-channel HDMI audio output, as explained in this interview:

http://ambisonicbootlegs.wordpress.com/2007/08/30/interview-with-simon-g...

A free download of a demo of the game is available now from the PS3 online service. It will work with 5.1 (e.g. Dolby Digital AC3) but a 7.1 system sounds better (as you'd expect). A simple headphone mode is also included.