Egypt, Tunisia, and probably another country or two soon, have thrown off long-time dictators, using peaceful methods. Gandhi got rid of British rule in India with nonviolence. Many other examples since then show the power of nonviolent protest.
The New York Times' article about Gene Sharp is interesting, and has some nice links as well. I've never heard of Sharp, so now I'll have to read his "From Dictatorship to Democracy" and find out what the fuss is about.
The most amazing thing about these recent protests is that they are efficient. There has been a lot of thinking and planning ahead of time. This is in contrast to 1989 when the Chinese protested at Tienanmen Square, and were crushed by the military. Shen Tong's book Almost a Revolution tells what happened there. They were not prepared for their small protest to blow up into such a huge demonstration. They had to organize and improvise on the fly. This caused all kinds of problems when the protesters tried to negotiate with the government, because it was difficult to present a united front and concrete demands when the protesters were so splintered.
On February 22 PBS will broadcast an inside look into the organizing and running of the protests in Egypt. This should be enlightening.