Black cats and broken mirrors: What’s your poison?

For whatever the reason, superstitions have been coming up in my conversations recently. I looked up the word to see the origin and was faced with something else. Apparently superstition is irrational. I don't know if I believe that. Now is that irrational? I have to chuckle.

Here are mine in no particular order:

$2 bills: I must get this bill out of my wallet as soon as possible, but I will put it in my wallet. It must be spent immediately!

Spilled salt over left shoulder: Because I am a server this happens a lot more often than it should.

Ladders: Don't walk underneath them. This might be a safety issue as well.

Knocking on wood: I am religious about this. It could just be that I'm a Minnesota sports fan. Hahah!

Wishing wells: I believe wishes here do come true.

I find this fascinating, so please let me know what your superstitions are. Anyone think superstitions are irrational? I think everyone has at least one. Also, if anyone could explain the yellow lighter thing to me, I could sleep at night.