Hegesistratus of Elis had once been arrested by the Spartans on the charge of doing them a number of injuries of a very serious nature. Flung into prison and condemned to death, Hegesistratus, realizing, in his desperate situation, not only that his life was at stake, but that he would be tortured before his execution, dared a deed which one cannot find words adequate to tell.
He was lying with one foot in the stocks--which were made of wood reinforced with iron--and somehow managed to get hold of a knife, which was smuggled into the prison. No sooner was the knife in his hands than he contrived the means to escape--and how he did it was the bravest action of all those we know: he cut off a piece of his foot, having nicely judged how much to leave in order to pull it free. Then, as the prison was guarded, he worked a hole through the wall and escaped to Tegea, travelling at night and lying up during the day in the woods. The Spartans went out in force to try to find him, but he got clear and reached Tegea on the third night. They were astonished at the man's daring when they saw half his foot lying by the stocks and yet were unable to find him.
I'd love to know what Hegesistratus did to annoy the Spartans. Whatever, it must have been spectacular.
Herodotus say Hegesistratus got himself a wooden foot made. He later went over to the Persians during the wars and became one of their seers.