This August the International Congress of Mathematicians (ICM2006) was organized in Madrid. The opening ceremony was attended by the Fields medals, the Nobel Prize in Mathematics, so to speak. The winning mathematicians were Andrei Okounkov, Grigori Perelman, Terence Tao and Wendelin Werner.
He has highlighted a name above all: Grigori Perelman. Perelman solved the first problem of the millennium, the conjective of Poincaré, and that is why he has been awarded a medal of Fields. But he has not received it. He has not even attended the congress, and has given much to talk about.