I like francopoli's response and I'm just going to add a couple things.

No matter how incompetent, stupid, ignorant, enraging, "she's-not-even-trying!" someone comes off as, try to remember you don't know everything about their situation. I think there's a quote, "Be kind...for everyone you meet is fighting a battle you know nothing about." Besides ramifications, you might end up being the ignorant one. Don't burn bridges, etc.

I've burned one bridge and I got purely lucky that he was truly a hack and incompetent and a lot of people saw it. But I still regret the way I handled the situation - even though there are no ramifications or anything that have put me in a situation where I should regret it. I work with a couple people who sort of know him or have done work with him and I wonder if their perception of me is in any way skewed by that incident, whether they know anything, etc.

thenewgreen told me when (I was talking to him about putting my two weeks notice in) to be as nice and kind and perfect as possible because it's never worth saying what I truly feel. He also told me to write a letter of resignation for my boss(es) and to my coworkers letting them know how amazing they are and how much I value them and everything. Both were excellent pieces of advice.

The satisfaction I could have gotten for a short moment of revenge and freely speaking my mind is nothing. It's petty. It's not worth it. In the way I handled my resignation, I've found myself so much more deeply satisfied by being the bigger person and handling it in the best way I possibly could. I wasn't expecting that. I look in the mirror and go "damn girl, you've grown up!" and there's a real power to that. Plus, I know if the world ends tomorrow, I'm still in a position where I could probably get my job back if I truly needed it. You never know what shit life will fling at you.

My father was 24 when he quit his first job, under strangely similar circumstances as me currently (grammar fail). He had a bit more of an ego than me (for a good reason) and handled it very differently than I did though. Three weeks later, his dad had a stroke and my dad suddenly didn't have 4 months rent saved or the ability to find and start a new job while taking care of his dad. He put his ego aside and went crawling back to his supervisor. His supervisor laughed in his face and had him escorted out of the building. Ouch.