I'm looking for people's recommendations on the best software to use for free computer-computer communication (ie skype). Popularity doesn't really matter as whatever I get I will tell a few friends to get and that will replace long distance calling for me. I'm mostly concerned about the sound quality. Any suggestions? The options I'm currently considering are google talk, skype or teamspeak but I am open to anything.

Googletalk works good for me.

I think I'll try that since I use gmail and they seem to be integrated now.