I can't believe I forgot this place. In addition to the wonderful letter by Robert Heinlein to Theodore Sturgeon was the incomparable
On December 5th of 1921, future-Nobel laureate and Pulitzer Prize-winning author William Faulkner landed a job as a University of Mississippi postmaster. Despite numerous reports of his writing novels on the job, losing and occasionally throwing away mail, ignoring colleagues and customers, playing bridge during opening hours, and regularly turning up late only to leave early, Faulkner somehow held the position for almost three years — until, in September of 1924, a predictably unflattering inspection resulted in him being forced to resign.
He wrote the following letter to his superiors.
As long as I live under the capitalistic system, I expect to have my life influenced by the demands of moneyed people. But I will be damned if I propose to be at the beck and call of every itinerant scoundrel who has two cents to invest in a postage stamp.
This, sir, is my resignation.