The action of unblocking someone and blocking them again on AIM in order to see if they're online. This is about the equivalent of knocking on someone's door to see if they're home, then your nerves collapse and you run the fuck away before they see you. Usually occurs after a terrible conversation, which ends up with one person blocking the other. Of course, this just makes the person they blocked attractive, so they make frequent spot checks to see if you're online.
paranoia bacon: i am so freaking awesome
rosesnguns17: what happened?
paranoia bacon: i just bitched out this hot-ass emo chick, and now she's block-checking me.
rosesnguns17: just make sure you videotape it :):):)