Gamification, love it or hate it, but every year thousands of developers try to collect as many "winter bash hats" as possible on StackOverflow and its sibling sites. In 2013, I collected 12 hats. In 2014, I collected 15 hats. But how many hats did I win this year?

Winter bash Stack Overflow 2015

This year, I collected 20 hats! Needless to say that I'm a sucker for gamification ;-)