Bruce Bawer has a fascinating essay on the life and achievements of Vaclav Havel. For those who may not know, Havel was a playwright who gave up a potential life of privilege as a government-sponsored writer to become a leader of the dissident movement in Communist Czechoslovakia in the 1970s. As a result, he spent years in horrible communist prisons. During that period, he also wrote The Power of the Powerless, in my view the best of all books on life in a totalitarian state.
After the fall of communism in his country in 1989 (thanks in part to the efforts of the dissident movement he helped lead), Havel became the first president of the new democratic Czechoslovakia.
As a general rule, I'm not a big believer in heroes. Many of the people held up as such actually do more harm than good. However, if any currently living person deserves to be admired as a genuine hero who really did make the world better through his courageous acts, Havel does.