He has, however, turned this prize down too!
The Daily Mail (sorry, it's the only article I can find!)
It was announced on 18th March 2010 (last Thursday...) that Grigori Perelman has been awarded the first Millennium Prize for his proof of the Poincaré conjecture.
Note bad for a proof that wasn't properly published by the author, a jobless man who (according to Wikipedia) lives with his mother. Although not many people have the opportunity to turn down a Fields Medal!
He has, however, turned this prize down too!
The Daily Mail (sorry, it's the only article I can find!)