[hetspookjee]

As a previous commenter said Terence Tao is a living genius currently. But also, some people that (somewhat) recently rose to fame in the field of mathematics are:

Andrew Wiles, for providing a proof to Fermat's Last Theorem.

Grigori Perelman (and Richard Hamilton), solver and winner of the Millenium Prize Problem: Poincare's Conjecture.