Daniel Shechtman was just awarded the Nobel Prize in Chemistry (2011). He discovered that matter can exist not only as crystals, which have a regular geometric arrangement of atoms, and amorphous non-crystals that do not, but also as quasicrystals which have a different type of atomic ordering.
The Guardian has an interesting article on Schechtman, whose discovery was roundly disbelieved by other scientists and he was ridiculed for years.
In an interview this year with the Israeli newspaper, Haaretz, Shechtman said: “People just laughed at me.” He recalled how Linus Pauling, a colossus of science and a double Nobel laureate, mounted a frightening “crusade” against him. After telling Shechtman to go back and read a crystallography textbook, the head of his research group asked him to leave for “bringing disgrace” on the team. “I felt rejected,” Shachtman said.
— Sample (2011): Nobel Prize in Chemistry for dogged work on ‘impossible’ quasicrystals in The Guardian
Hat tip to M. Eisenberg for this link.