Mumble is voice communication software designed for gaming. It is similar to Ventrilo and Teamspeak. Come join & play with the community and have fun. If you have any questions or need help please contact the admins by using the forums.
Online list: http://voice.sc2gg.com/
Forum Post: http://forum.sc2gg.com/index.php?topic=13543
For official help & downloads: mumble.sourceforge.net