I read John Gribbon's In Search of Schrodinger's Cat recently and have spent many moments puzzling over the implications of QM. Particularly this passage: Imagine an arrangement that records which hole an electron goes through but lets it pass on its way to the detector screen. Now the electrons behave like normal, self-respecting everday particles.We always see an electron at one hole or the other, never both at once. And now the pattern that builds up on the detector screen is exactly equivalent to the pattern for bullets, with no trace of interference. The electrons not only know wether or not both holes are open, they know wether or not we are watching them, and they adjust their behaviour accordingly. It's like god got lazy planning the laws of the universe: Oh screw it, they'll never see this little ad hoc thing I did there. In fact, I think it works nicely, I get to seem a little ecentric, and if they accuse me of being irrational I'll accuse them of not being multi-dimensional!