I was raised with superstitons. What a fun post. I have enjoyed all the responces!
Some that I was taught not mentioned earlier : drop a dish towl while drying dishes and you will get company, don't put your hat on a bed - bad luck..don't pass any one one the stairs- bad luck ( school stairs were so stressful during class change) don't sing at the table-bad luck ( happy birthday song always confused me on that one) , say "bread and butter" when walking side by side and a sign or person comes between the two of you.
These are all off top of my head beyond already posted ones. Wow, as I think about this....how stressful to have so much to respond to while growing up! Ha ha!