Looking at someone in a creepy fashion in order to make them uncomfortable.
Friend 1: Did you see that guy in the car next to us at that stop light? He was totally staring.
Friend 2: He was definitely skaggin it.
Friend 1: I'm uncomfortable.
To be so incredibly drunk and/or high to the point where one must abruptly take a massive dump, unexpectedly vomit, and then inevtiably pass out. In that order.
"Dude, that guy sure is messed up tonight! He made a big fool of himself."
"Yeah, he's got a bad case of the Nasty Skaggins."