Here's a blog with some prize-related posts (most with some space prize aspect or other):
Gingrich Kerry debate climate change and prizes
Save Lives and Win Fabulous Prizes Grainger water-filtration prize
NetPrizes NetFlix Prize
Prize Watch list of prizes they're checking, most either space-related or X PRIZE Foundation prizes
Shafting the Space Elevator NASA and the space elevator concept - note that since this point, Centennial Challenges has committed to a series of tether and beam prizes with larger prize purses. Also note that NASA is *not* specifying the space elevator as their way to get into space. They offered prizes for tethers and power beaming, which have a variety of near-term potential uses in space with NASA and commercial applicability. The Spaceward Foundation that is administering these prize competitions for NASA is packaging them as Space Elevator competitions for their own purposes. It's a win-win for both.
NASA Wises Up ... Sort Of Replacing the Shuttle with a capsule design instead of letting the private sector do it
A Prize No More X PRIZE won
How Prizes Change the World thoughts on the X PRIZE and innovation prizes in general