Its Taboo
 

They're annoying, they're important, and every culture has them. Taboo's, things that you just don't do in polite company for one reason or another. I'm curious about some Japanese specific ones as well as other forms of etiquete than a world travler should know.

I may as well explain why this came to my attention. You see, my family has a habit of uncovering these social landmines, and we don't just trip them we flop down right on top.

Case in point: I was invited the family home of a friend, they happened to be Indian immigrants. Thinking myself rather cleaver I got a gift for her father a gift to show respect, forgetting the sacred nature of cows and later violating nearly a dozen lesser known customs...long story short. Father is mad, family is laughing, friend is embarrased, and wilson is terrible. Something similar happened with my dad and some Ukrainians.

I'm hoping to avoid this when I hit Asia so it would be much appreciated if you could give me some customs and maybe reasons why they exist.

Don't use a toothpick out in the open. Cover your usage with your free hand.

Don't walk on tatami mats with shoes on - I knew this and completely forgot the first time I encountered a tatami room =/

Careful what you do with chopsticks - don't wave them around, point at people with them, pass food to/from someone else using them or leave them sticking upright in a bowl of food.

Don't stick your chopsticks vertically in a bowl of rice, lay them horizontally across the bowl or on one of those chopstick rests. Be very careful with this. In Chinese and Japanese tradition, sticking chopsticks into a bowl of rice means you're going to offer it to the dead. ^.^;

Don't ever say at the 100-yen shop, "Excuse me! How much is this toothbrush?"

Ohhh I used to work in a $2 shop, and people who did that annoyed me so much! The funny thing was that they weren't just people being idiotic on purpose, plenty of people simply didn't make the connection.

Uhh isn't this question already answered 874523645872 times?

Oh wait you made it 'funny', that's fine then.

but not everything in a 100yen shop is actually 100yen

Something you are allowed to do:
Slurp while drinking soup, eating noodles, etc :D

Did you really think I didn't know that? You're responding to humor with science! ;)

I searched the forum archives and got bored of shifting through the masses of information after about 5 min. So I took the lazy mans way out and made my own thread.

But in other news, thanks for the feedback. The information may seem basic to those of you that have spent more time studying the culture but I'm greatful for any knowledge I can get.