In 1735, the French Academy offered a prize for the solution to a certain astronomical problem. The problem was deemed so difficult that many mathematicians expected several months to pass before an answer was produced. Leonhard Euler was not among them. Having became obsessed with the problem, he worked continually for three days, produced a solution, and won the prize.
Unfortunately, poor working conditions and intense stress led to the loss of one of his eyes. Though still in his twenties, however, Euler took the loss in stride: "Now," he declared undaunted, "I will have fewer distractions!"
[Euler became completely blind at the age of 60 -- and continued to produce mathematical work for another 17 years.]