Ambisonic.net - An alternative method of surround sound encoding, with technical articles, discography of ambisonic recordings, equipment listing, FAQ, and the Sursound mailing list. - http://www.ambisonic.net/
TalkBackwards.com - Upload a song or voice recording and hear it played backwards online to see if it contains any hidden messages, or just for the fun of it. - http://www.talkbackwards.com