Sisyphus, Greek Sisyphos. Mythological king of Corinth who was said to be both cunning and violent. He is mentioned both in the Illiad and the Odyssey. He was the son of Aeolus (Eolus), the God of winds, and Sisyphus himself has sometimes been attributed as the father of Odysseus.

The most famous story about Sisyphus is the one about his death and eternal punishment. When Death came to bring him to Hades, Sisyphus put Death into chains, which resulted in that no one could die. Luckily for Death - but not for the rest of us -, he was released by Pluto, who sent the God of War Ares to unchain him. This done, Death forced Sisyphus to come to Hades. But the clever king had pulled one more trick on Death; he had prepared his departure so that Death had to let him return to the living to avenge his wife before returning to Hades for ever. This was because she - on his orders - had neglected to bury him properly. But again back in life, he did not avenge his wife nor return back to the underworld. Instead he continued to live on his life until he died many years later a second time.  

For having fooled Death not once, but twice, the almighty Zeus decided to give Sisyphus the ultimate punishment: endless, futile labor. He had to roll a stone up to the top of a mountain, where it would roll all the way down again when it reached the summit.

From this, we have the expression "labor of Sisyphus" for seemingly endless and meaningless tasks.

Albert Camus wrote an essay in 1942 on the fate of Sisyphus, called The Myth of Sisyphus. Camus's idea was that Sisyphus instead of regarding his whole existence as absurd, the found meaning and happiness in the work itself, as he writes:

"The struggle itself toward the heights is enough to fill a man's heart"