I first saw this ball thingie in the Jackie Chan movie, Armour of God. I have always want to try one out and I had heard a while back that there was a Danish group that put you in one with a little water so you can float/stay level and you would roll down a hill.
http://www.youtube.com/watch?v=C-dDAaKculk

Cool paper display tech.

I only agree with some of the things that the poster talks about.

http://www.youtube.com/watch?v=g8j8JZecaxI