The only things I can definitely think of off the top of my head is the length of time the brain can be deprived of oxygen before unrecoverable death (five minutes), and a bunch of random stuff about Japanese culture. For instance, you do not ever stick your chopsticks upright in a bowl of rice, because that's a ceremonial thing at funerals. For the same reason, you don't pick up something with your chopsticks at the same time as someone else, because that's the way you pick up your dead friend's bones after the cremation. (Yeah, Japanese funerals are kind of weird.) Also, the word 'four' in Japanese is pronounced the same way as the word 'death', and most buildings don't have a room 42 because four+two is pronounced the same as 'die'. And samurai who didn't have a lot of money knitted socks in their spare time to sell.