The act of making yourself look like a snail in funny places; it is done by lying down in a similar fashion to planking, but with your butt raised up in the air.
"I'm snailing! Y'know, it’s where you make yourself look like a snail in really funny places. It's way more hardcore than that stupid plankingcrap!"
When a girl saddles her beef curtains around a schlong and slides from tip to ball sac, then back again before meat handling the head and taking the high hard one all the way home.