"Ideas cant be copyrighted" Doesnt mean you need to be rude about it. If "dremel"'s thing inspired this, there's nothing wrong with saying so. If he didnt, there's no reason to say you didnt, even if a bunch of nerds say otherwise. Also, its Powdertoy; like most things that dont matter, nothing about it matters in the long run, so why get worked up about who owns what or where things came from?