Challenge.gov

Has anybody checked out this challenge.gov site?

It's a whole bunch of challenges offered up by various organizations and winners usually get cash prizes. There are some challeneges on there that I thought some of you might be interested in. I've only browsed a couple of pages in and I already found three interesting competitions. One was from NASA about creating an idea for a rover robot that can grab a sample and safely return it to earth. Another one about artificial intelligence and a third about getting a "nano" payload satellite into earth orbit (less than 1 kilogram) on a small budget. Top prizes for best ideas are like $2 million U.S. and I don't see anything that restricts most of these to U.S. Citizens.