Thomas A. Edison

At around the age of 12, Edison started to lose his hearing. One legend has it that a train conductor smacked him in the ears after he started a fire in a boxcar by doing experiments. Edison himself said that he was injured when the conductor picked him up by the ears onto a moving train. Others had said that it caused by a bout of scarlet fever during childhood. In all likelihood it was a genetic condition as both Edison's father and one of his brothers also suffered from hearing loss.
But one thing's for sure: Edison actually liked being deaf (technically, he was hard of hearing, not completely deaf). He said that it made it easier for him to concentrate on his experiments.
Oh, one more thing: Edison actually did have a laboratory in a boxcar that caught on fire! Then 12-year-old Edison took a job selling newspaper and candies on the Grand Trunk Railroad from Port Huron to Detroit. He set up a lab for chemistry experiments and a printing press in the baggage car, where he published the Grand Trunk Herald, the first newspaper published on a train.