The whole of the main tune is written such that for every three notes in the left hand, you have to play four in the right. Takes a while to get used to it, and it the rhythm gets drummed into your brain a bit - I keep finding myself doing it on tables, desks and the like. Hope that made sense this time.
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Listen to a rare love song (they dont make many love songs) by nine inch nails called With Teeth. The piano and guitar piece near the end is my favorite piano piece.