WebRTC is the future of Web communication if the W3C has anything to say about it. It's an HTML5 technology that turns your browser into a video/audio communication tool. The only problem standing in its way was that it would only work if both users were on the same browser, but the folks at Mozilla and Google have found a way around it.
Google and Mozilla jointly announced the RTCPeerConnection today that brings interoperability to WebRTC clients on both Firefox and Chrome. This will allow users of either browser to engage in video/audio chats by just using the power of the Web instead of relying on third-party plugins.
You can check it out in action below:
RTCPeerConnection is currently available on the Chrome 25 beta and the latest build of Firefox Nightly. Once you download one of those, set the media.peerconnection.enabled to true in about:config and you'll be set.
For the developers out there, Mozilla has a lengthy tutorial on how to bring RTCPeerConnection to your apps at its blog post. Check it out to get all the details.