When u go outdoors and take a leak.. aren't ya supposed to say "Excuse Me" so that the spirits don't get pissed at ya and possess u?
And partially so that you're not pissin' on their grave or something...
Also heard you're not supposed to pick up foreign objects in foreign places cuz you don't know where they've been and it could be bad luck or possessed by a spirit :alienface
Just a superstition I heard..