clan chat[SOLVED]

i know sometimes that playing with your clan mates you have to say something like "wath out theres a ghost behind you" but you dont have time to type it up
(some clans require you to have a headset)
using phones is not convinient because you can talk to one person at a time

what im asking is:
what program can i use to talk within my clan using a webcam but without the video, i know the other clan mates will need to have the same software installed