"Rocket Talk is a free Internet voice message system. It allows anyone with a PC to send voice message to anyone else on the Internet to either a Rocket Talk user or to an email account, any email account." What you need to get started is a 3 and a half megabyte file you can download from rockettalk.com. Why would you want to send voice messages instead of regular old email?
"It's a more natural form of communication. There's a lot of subtleties, there's a broad scope of emotion that's carried with a single sentence. And using voice, you can certainly convey that. Even if it's just one sentence."
Voice can also solve another big email problem. You can send messages in other languages easily...
"There's more languages than there are keyboards. And certainly everybody can talk. So talk is the easiest way of communicating."
Again, you can give it a try for free at rockettalk.com.