If you flip a coin, you'll have equal chance (50-50) of getting head or tail, right?
Wrong. Stanford math professors proved that a flipped coin will land as it started 51% of the time.
source: Persi Diaconis, et al. Dynamical Bias in the Coin Toss [PDF] (2004)
By the way, Persi is a very colorful character who once proved that 7 shuffles is all you need to get a random deck of cards.