Research, research, research - google, do whatever you have to - ask people. Then, when you think you've done enough and you can't find anything like it, as the Canadians say 'Give 'er!' Don't forget that today it's rare that an idea is original - someone's either already had it or is going to have it - there's so many of us and only so many orginal ideas to go around in this great big world so inevitably, there's going to be great minds thinking alike.'
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