V; A rather intense form of head banging used by moshers in the pits at Brutal Metal concerts. The moshers all line up against a fence, and head bang into it, tearing up their faces, spraying blood everywhere, and in some cases, dying. Usually accompanied by a visit to the ER right after the concert.
"Why is your face all fucked up?"
"I was Fence-Banging at the WCWBT concert last night."