Mumble has the least observable latency. (Requires a server) (Free)
Teamspeak has the most polished client. (Requires a server) (Costs)
Skype. (No server required but needs an account on the service) (Free)
Steam is usually on most gamers PC's. (No server required but needs an account on the service) (Free)
Windows Live Messenger. (Useful as a backup but requires a Hotmail/Xbox live account) (Free)
When I run my own server I use Mumble because it's free. When I play certain games with friends we use a TS3 server that someone in the group rents. Outside of that I use Steam.
Teamspeak has the most polished client. (Requires a server) (Costs)
Skype. (No server required but needs an account on the service) (Free)
Steam is usually on most gamers PC's. (No server required but needs an account on the service) (Free)
Windows Live Messenger. (Useful as a backup but requires a Hotmail/Xbox live account) (Free)
When I run my own server I use Mumble because it's free. When I play certain games with friends we use a TS3 server that someone in the group rents. Outside of that I use Steam.
(it was the first voip i used to play games with)