To walk up behind someone who is sitting in a chair or otherwise at crotch level and poke them in the back of the head with your three-inch wood. Named after a preverted math teacher who we called Der Fuehrer. Is a form of frottage, which Japan, the birthplace of hentai, bukakke and the professional cripplefight, has recently begun to crack down on.
Der Fuehrer: Is the server back up yet? (trys to DerFuehrerPlex me)
Me: (hunched over table to avoid his three-inch wood) No, it's still crashed by your massive Armada of Soviet Schoolgirl Porn. And dry-humping the back of my head isn't gonna help.