8. Broken Dishes - Denmark
Waking up on New Year's Day to find your front door pelted with broken porcelain would not bring joy to the faces of many Brits, but in Denmark, it is typically a sign that you've got plenty of friends. Throughout the year, Danish people hoard old china, which they save for the end of the year, and then on December 31st, they run around to the homes of their friends and smash them at their front door. As a result, the more broken china you find outside your home the next morning, naturally the more friends you have. One wouldn't like to be sticking around for the clean-up process, though; hungover folk scarcely managing to keep upright trying to clean up broken shards of porcelain. Sounds very safe.