I dont know what saltpeter is, but if you wanna play a joke on your roommate, throw some methylene blue in his beer. it wont hurt him at all, but he'll pee blew for a day or two. very funny stuff.

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I don't do this for my family, my friends, women, accolades, pride, or ego. I do it for me and no one else, its just part of who I am.