Michael Caine spent eight years trying not to blink because of advice from an acting book
The practice earned him the nickname "Snake Eyes," so it was definitely worthwhile

Michael Caine CBE, perhaps angling for a lucrative Visine sponsorship, has revealed that one of the secrets to his acting success is that he once spent eight years trying never to blink.
Prompted by an interview question we’re saddened hasn’t been recorded for posterity, Caine recently told The Mirror that he read a book called Teach Yourself Film Acting which gave him the idea that not opening and closing your eyes in accordance with nature’s whims is a solid acting technique. Caine says he put the book down thinking, “Don’t blink. You must never blink” and then proceeded to spend the “next eight years” of his life “[walking] around trying not to blink.”
He says the practice earned him the nickname “Snake Eyes,” which is probably cool enough to warrant a lifetime of red, sandy peepers, and also probably freaked the hell out of everyone he knew.