A version of the noVNC client is available online here.
A convenient shortcut address is noVNC.com
It's not a real project until there are videos and screenshots.
This online demo plays back a recorded VNC session.
There are many companies/projects that have integrated noVNC including Ganeti Web Manager, OpenStack, OpenNebula, and LibVNCServer. See this wiki page for a more complete list with additional info and links.
A browser with at least minimal canvas support (i.e. not IE 6, 7 or 8).
Run a vnc server, run the WebSockets proxy, load the page, and connect! See the project README for more details.
You can also clone the project with Git by running:
$ git clone git://github.com/kanaka/noVNC