By the age of 29
by Mangesh
Gary Larson: After working in a music store and playing his banjo for years, Larson decides he hates his job and starts submitting comics to the Seattle Times under the name Nature’s Way. That strip was later retitled The Far Side.

Shel Silverstein: By 29, Shel had already written a book, recorded a music album, and was regularly contributing articles to a young Chicago magazine called Playboy.

Roald Dahl: Had already served as a pilot in WWII, crashed a plane, lost his eyesight, regained his eyesight, and published a kid’s book.

John Cleese: Earned his law degree, had been in a few successful revues, and was one year away from starting Monty Python.

Woody Allen: Had been writing one-liners and comedy bits for shows like Sid Caesar, Ed Sullivan and other comedy greats since age 19, and was just starting to perform his own stand-up.

Bill Watterson: Just two years into drawing Calvin and Hobbes, the elusive Mr. Watterson had already won the Reuben Award for Cartoonist of the Year (he won it around 28, and is - I think- the youngest recipient of it to date).

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