I was standing in a queue behind a woman waiting to be served in a shop the other day. The woman took out a five dollar note to pay for her purchase. It had a tiny tear in the corner. The sales attendant refused to take the note and there was a bit of a stand off until another employee told him that it was ok to accept it. Surely a tiny chunk missing from the corner doesn't invalidate the note?! I get more annoyed when I end up with one of those pesky New Zealand 20 cent coins.