Time for an update!
This is one I like when I used to be heavier whenever someone called me fat in a mean fashion:
"I may be fat, but you're ugly and I can always diet!"
I may be on the small side now, but I tell heavier friends that one whenever they get upset about someone commenting on their weight, and they like it alot

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On the note of being made fun of or judged, I came up with the following:
"Your existence must be terribly boring if you've got nothin' better to worry about than what I'm doin'."
This was good especially in high school, when the troublemakers would tease me for "not having a life". If getting high/drunk and getting lucky is considered havin' a life, I'd definitely rather not have one

:.
Some more of mine:
"It is better to do your own thing and worry for just a moment what others will think than it is to go with the flow and constantly worry about what others will think."
"It's a waste of time to worry about what others think. They don't do it too often!"
"Shallow minds talk about people, decent minds talk about events, and brilliant minds talk about ideas."
