Updated - see below
On a rare visit from Jacky last summer, he was telling some of us about a program one of his colleagues (they're graphics PhDs at the University of Toronto) was creating, that was a physical interface for GUI desktop management. Basically, instead of having a computer desktop filled with icons, you can interact with files and icons like physical pieces of paper, and piles of paper.
Fast forward roughly a year, and David Pogue blogged about seeing BumpTop at the Technology, Entertainment, and Design, or TED, conference. Which is what Jacky was talking about (I'll probably update this with word from him). They have a video on YouTube, included below.
It seems really cool, but Pogue's (and other commenters') issue is that this may not be all that practical. But it is really novel - I can see why Jacky was into it, and would bring it up. In Pogue's post it also states that at the TED conference, BumpTop was demoed using a laptop, not the tablet interface shown in the video.
Update: Got word from Jacky, with a couple of interesting notes. I'd missed the best video, the Hip-Hop BumpTop video ("There's physics on this desktop, it's 2 1/2 D..."). He also mentioned the BumpTop website, which I forgot to link to in the first run. That's the kind of shoddy blogging you get when you blog at work.