MAN OF THE DAY

Very Cool: Proving the Poincare Conjecture.

Even Cooler: Ignoring the prize money. "Known for his single-minded devotion to research, he seldom appears in public; he answers e-mails from mathematicians, but no one else."

Coolest: Revolutionizing mathematics. "While working out the Poincare Conjecture, Perelman also seems to have established a much stronger result, one that could change many branches of mathematics. Called the "Geometrization Conjecture," it is a far-reaching claim that joins topology and geometry, by stating that all space-like structures can be divided into parts, each of which can be described by one of three kinds of simple geometric models. Like a similar result for surfaces proved a century ago, this would have profound consequences in almost all areas of mathematics."