I heard a song when I was 14, years before I ever tried to be a musician. I liked the song and listened to it a lot then, but not since. About ten years later, I tuned my guitar to a G for the first time, and low and behold, the whole song came out. All from a distant memory just because the G tuning was so distinct.

I don't know how many times I'd sit and try to be creative with an instrument, start a riff, and watch it turn into a melody that already exists. Anymore I just ignore that its like something else and make it my own. Whew, that sounds kind of like Bill Gates....