This should seem like obvious advice to most of us, but apparently to some writers it hasn't sunk in: don't be a jerk to editors you're pitching to, networking contacts, or anybody who you come across in your writing career. If you're not sure who might affect your writing career and who might not, it might be a good general policy just to try not to be a jerk at all. Angela Hoy recommended this on Writers Weekly and for some reason, it offended the jerks out there who demanded their right to be jerks.

This does come up. For some reason, some writers think it's acceptable, perhaps even attractive to give attitude. I am friends with editor at the Onion AV Club, who tell me that it's not uncommon to receive letters that run along the lines of "The Onion sucks. You should let me write for it."

Most infamously of late is Peter Braunstein. Gawker reported on the incident of him allegedly raping a woman after posing as a New York City fireman, and then found a Rolling Stone editor who revealed Braunstein's own special way of pitching stories. I'm not going to say that being rude to editors lands you in jail, but look where it (amongst other more heinous crimes) got Braunstein.