Best Web-Based Voice Chat?

I used to use all the time to get LoL teams organized, but for some reason, it refuses to work for me any more. Is there anything else like it as in I can give people links to the chat and they don't have to sign up and I'm able to kick / ban people and the works?

does it have to be webbased? mumble is pretty good.

Yeah, I know about Mumble, Ventrillo, Teamspeak, Skype, ect.  I was really hoping for a web based chat so I could link people rooms for League