Sometimes stylized as "run up, get done up". It is a warning given out to those that seem to be contemplating making a violent move against a person or group.
Run up, in this situation, is referring to someone "running up" on another person with the intention of fighting or jumping said person.
In the given context, Done up refers to someone being on the receiving end of a beating.
To put it simply, it means "You can run up on me and try to attack me if you would like, but if you do I'm going to kick your ass."
"Do I look fucking scared to you? Run up and get done up, pussy!"
When you have to pee in a movie but don’t want to miss anything, and must do the following mental equation: will the amount I have to pee cause enough discomfort to diminish my attention capacity for the remainder of the movie to an extent which is greater than the amount of the movie I would miss by making a mad dash to the restroom.
I saw Satantango last night, wonderful film but by the 5th hour I had to start doing pee calculus.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).