Public toilets: At best, they’re functional, at worst, dirty, dark and even unsafe. But in Shibuya, a busy ward in Tokyo, officials want public toilets to inspire wonder. They’ve recently started a tour of 17 bathroom facilities designed by world-class artists and architects. One is housed inside a glowing cube, another resembles a fairy-like woodland dwelling and, yet another toilet, operated by voice, will clean your backside on command. The World’s Patrick Winn reports.