Open Source Alternative to Teamspeak (TS) and Ventrilo (Vent)

Looking for a open source cross-platform alternative to Teamspeak (TS) or Ventrilo (Vent)? Check out this project for a great gaming VOIP solution;

"Mumble is an open source, low-latency, high quality voice chat software primarily intended for use while gaming."

Gentoo have recently masked Teamspeak client/server due to security issues because it contains Internal copies of vulnerable libraries.

So now a great time for you to discover a true open source alternative!