Today a friend at work needed a small philips head screwdriver to change the batteries in a calculator. I got my Swiss Army knife out of my pocket and opened up the Philips head screwdriver/bottle opener. When he returned it to me, he had it still open and asked me if I was superstitious. I knew something was up, but didn’t know what it was. He explained that there is a superstition that if someone gives you a knife open, you are supposed to return it open. If they give it to you closed, you are supposed to return it closed. I had never heard of that, but another person who saw what was going on confirmed he had been taught that too.
I tried to look this up and see if I could find the origins of it, but all I found was that it is apparently a southern thing. I also found another superstition that it is bad luck if someone gives you a knife because it will supposedly sever the relationship. But you can mitigate the bad luck by “paying” for the knife by giving them a quarter. I thought that was pretty funny.