The act of frummelling beings by shaking a tinned beverage, usually a beer and usually of the longer tinned variety. After a healthy dose of shaking, the frummeller carefully places each hand on either side of the beverage getting it parallel to the ground. In one vigorous motion, the frummeller hastily lifts his hands towards his forehead whilst performing a headbutt aimed at directly at the middle of beverage, the aim being to split the tin in half. Only one attempt is allowed. Frummelling normally takes place in groups so that if one person fails, the beverage is past on until success is reached. If particular penchant and skill are displayed by quick dispatch of the tin, participants may earn the coveted name 'cone head'.
'Guys, i've got a spare tinny, fancy some frummelling?'
'Never seen frummeling like that, what a cone head.'