Talk about male bonding! Have you ever gotten together with your buddies, stripped down to your thongs and paraded around the neighborhood? In groups of 10 to 12 people at night? In midwinter? No? Well, get with the program -- men in Okayama have been doing this for 400 years. Since I know you are dying to do this, I will tell you about the Naked Festival at Kannonin Temple in Saidaiji, Okayama Prefecture.
On the third Saturday of every February, on what is somehow arranged to be the coldest day of the year, this festival, called "Hadaka Matsuri" (or technically "Saidaiji Eyo"), causes the local men to drink large amounts of sake, strip off their clothing and adhere a "fundoshi" loincloth. They keep warm by jumping up and down and chanting "Washoi!" which means, according to the drunk man who was standing next to me, "Wondafuru!"
At any rate, it definitely means something encouraging and serves as a method of keeping warm, since the men chant "Washoi!" nonstop for hours at a time. Now I know why the Japanese don't have central heating in their homes. The secret to keeping warm is to just drink sake and jump up and down naked while saying, "Wondafuru!"