some dude at work for year never chipped in for buying soda... He would always drink it all that night and leave nothing for the people who chipped in for the following morning. So one day when we bought the soda, i took a little out and pissed in it to fill the bottle and I put it back in the fridge. The next day that guy told me "yo that soda was mad flat!!!" Hahahaha... victory is mine!