A bloody odd cell phone accessory--a strap that displays your blood type for all to see--is apparently quite popular in Japan. But lest you think it was invented to aid victims in the event of a medical emergency, it more commonly serves as a sort of relationship road map in a country that views ABO blood type as indicative of personality and romantic compatibility. You know, "You're an A, I'm a B, wanna go out tonight?"

Dating services in Japan use blood type to make matches, employers use it to evaluate job candidates, and morning TV shows and newspapers there regularly feature blood type horoscopes. "They use it like people here follow astrology," confirms my colleague, Download.com Senior Associate Editor Seth Rosenblatt, who lived in Japan for three years. "But of course its origins are in eugenics, which is much more sinister."

The charm--which sells at Tokyo's Strapya World for about $6--looks like a mini IV blood bag with a letter (A, B, AB, or O) written on the exterior. Fortunately, the red fluid on the inside isn't the real thing.

via [cnet]