I got my hands on a beta of this a while back when I had a touch screen to test it on but they have a full release now:

You can make piles of files and arrange by keyword in to piles, you can put photos and notes on the walls, simply throw a picture at the Facebook icon to upload. (full feature list)

Video:

You can download Bumptop here: http://bumptop.com/ (There is a free feature limited version, Pro is about £18)

I hope they release a linux version of Bumptop as it would be a good addition to compiz.