Cayne mentioned a week or two ago, and I've just had the opportunity to take a look at it, and interact with it. I quite like it as an alternative interface (maybe it has potential for rsi sufferers) but I'm so used to clicking now that it would take me a while to get used to it in more than a demo. I find it quite elegant, and some of the site design concepts are lovely - choose Communicate, The Links and use the circular menu navigation.

Another interesting interface is Fold n Drop which Richard pointed me at.

A couple of interesting interface design concepts.