Superstitions and stupid beliefs

OK, so we're all familiar with the crazy shit Koreans believe in:

~Fan death- If you turn on a fan without opening any windows or doors, you will die.
~Kimchi is to Koreans as Windex is to that Greek guy in the movie- Kimchi is both a preventative and cure-all for everything from the sniffles to swine flu to plague.

I know there's more, but I'm still new here.

So I was thinking today, surely the states have some similar bizarro cultural beliefs. I had a hard time thinking of any, but I came up with a short list:

~Tapping a can of Coke will decrease the amount of fizz.
~Shaking a Polaroid picture will help it develop faster.
~In my home town, kissing your hand and putting it to the roof in the car when you drive under a yellow stoplight will help you accumulate "good sex minutes" for some imaginary bank.

But the difference is, nobody genuinely believes this. We all know it's just silly superstitious stuff. I know my grandmother's generation believed living under power lines could give you cancer or something, but that belief has died out, as far as I know.

The only thing I can think of are a few diet-related myths such as going to sleep shortly after eating will make you gain weight (In truth your metabolism is slower at night, but that doesn't change how many calories you've consumed and burned over the course of the day. The value of a calorie is not dependent upon time.) But anyone who reads health news will soon learn otherwise because there is a lot that has been published about the truth of things.

Koreans really believe their crazy things no matter what anyone tries to tell them otherwise. Is there anything like that back home? Anything at all?

(And yes, I know I'm ethnocentric and ignorant of many things. However, the latter is something I work to improve, so it's all OK.)