osprey, this guy basically got a pint glass, stood it ontop of two ashtrays, a mobile phone and a box of matches and bet people that the circumference of the glass was more than the height.
Everyone was like 'no way - the height is far more' so he measured it buy wrapping a tissue/napkin around the top and marking where it met. Then he dropped it down by the side of the glass and it proved that the circumference was indeed larger than the height.
It turns out that the height of your average pint glass is 15cm whereas the circumference is 27cm so as long as your pile of ashtrays etc plus the glass is less than roughly twice the height of the glass, you should win the bet.