The fundoshi is a traditional Japanese male loincloth, made from a strip of cotton cloth, one "shaku" (traditional Japanese foot, 35 cm = 14 inches) wide and about 2.4 m (92 to 96 inches, = "six-foot", hence roku-shaku) long, which is twisted to create a thong effect at the back.
It went on to say:
Fundoshi are still used as traditional swimsuits. In some high schools, boys do the long-distance sea swim wearing the fundoshi. The present Crown Prince of Japan also swam in fundoshi in his childhood. In the pools and beaches of Japan, fundoshi swimmers can still be seen.
Fundoshi are still used as traditional sports underwear; like a Jock strap the rokushaku fundoshi is tight on the scrotum and lifts the penis to the side upwards positions.
Needless to say the reference to underwear and jockstrap got me interested.
I found a guide as to how to tie a fundoshi here. It looks pretty complicated so i think I'll stick to my jockstraps and thongs for the time being.
But the best thing I came across was naked toyko whcih describes itself as:
Naked Japanese male celebrities revealed, onsen photos and pics from Japanese naked festivals. This blog is intended for adults who appreciate Japanese male beauty.
Check it out - it has some great photos of naked Japanese guys. I didn't realise Japan was so open and fun. Here are some photos from the site: