Loudtalks Lite (previously known as free Loudtalks), the free push-to-talk for PC and Windows Mobile devices, is the fastest way to communicate online. You don’t need to type or call — just push the button/key and speak.
You can talk to all people in a group at once or anyone individually with a single button push, re-play the entire conversation later from the history history, or use it as your own PA system at your home/office. It’s just like a two-way radio!
Loudtalks Lite can even be installed on USB drive. Loudtalks will recognize that and will work in portable mode leaving no trace on host computer. Loudtalks has been translated to 11 languages, and is a freeware.