The Japanese are renowned for their technological prowess, and it is little surprise that they have applied their acumen to personal hygiene. Compared to the Nippon, we are uncouth Neanderthals, and these inventions prove it:
Toto Rectal-Cleaning Toilet:
Ever since Thomas Crapper invented a toilet that cleans itself (flushes), it was only a matter of time before an anal hygienist devised one that would also clean its user. The French have had their bidets for a while, but these are a separate entity. Now, Toto brand toilets, with built-in rectal washing and drying are the salient "western-style" receptacles in Japan, and in urban areas have even come to outnumber the traditional squatting-style toilets. While prudish types may find the experience more intrusive than invigorating, its hygienic efficiency is beyond question.
Halitosis-detector:
In a land where blowing one's nose in public is taboo, halitosis is unforgivable. And Japanese cuisine only exacerbates the situation, with the propensity of such ingredients as dried fish to fester between unsuspecting teeth. This is why in 1999, Tanita released the Fresh Kiss HC-201. Users blow gently into the device, which then rates the offensiveness of their breath on a scale ranging from 'undetectable' to 'very bad halitosis.' As its name indicates, the Fresh Kiss specifically targets Ganguro guys and gals looking to pull. But it has also developed a niche market of businesspeople, who don't want the remnants of a power-lunch to overpower potential clients.
Sony AIBO:
Not a piece of sanitary technology per se, but Sony's digital dog is certainly cleaner than a real one. Unlike their organic counterparts, the AIBOs do not liberally shed hair or feces. Moreover, given extortionate real estate prices in urban Japan, cramped living spaces are ill-suited to real pets. Computerized canines are now available in several breeds, with Apple's new iDog challenging the AIBO for market share and owner affection: users can synchronize it with their iTunes, and even program it to dance along. For the hectic Nipponese pace of life, these pets provide a physically and emotionally sterile alternative to man's best friend.