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2. Where do you get off?
A question asked when someone has done something considered to be awkward, strange, and/or just plain odd.

A rather literal analogy: When on a city bus/train/subway/etc., you might meet some odd person. You might ask "Where do you get off?" as in asking what stop they get off at, wondering if they live in a neighbourhood with strange folk.

Probably not the true origin of the term, but that seems like a pretty good guess if you ask me.
Guy 1: "So yeah, I like to run around naked with a ball of wool in my hand, and my cat chases me trying to get the ball of wool. It's sooooo much fun!"

Guy 2: "Where do you get off?"
1. Where do you get off?
1. (inquiry) Used when someone has crossed the line, in your opinion.

2. One of the very funny Lines from the very unsuccessful film Hot Rod
1. Friend 1: DUDE I JUST TONY DANZA'D YOUR EX GIRLFRIEND!
Friend 2: Where do you get off?

2. Rod: Where do you get off?
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