Yes there are plenty of people out there with way too much time on their hands - I am one of them - and these people will do some crazy things. We can thank / blame those at Guinness World Records for giving these people some direction and purpose.
When around 1,500 Belgium students came together at Ladeuzeplein square in the name of 'science' - Guinness was on hand to record it all. Dressed in their raincoats, the students eagerly awaited their cue. When the horn sounded, thousands of Mentos were dropped into the Coke bottles before them, and sugary explosions rained down on all! I'm not really sure how scientific the day was, but the enthusiastic crowd did break the world record for Mentos fountains. Hooray....
Another Crazy World Record
More Stats +/-
Top 100 Packaging Ideas in June
Crowdsourced Political Platforms
Hot Air Balloon Beds
Edible Fish Billboards
Comparative Baby Food Ads