The SatNav in your car calculates where you are from signals it receives from satellites orbiting Earth. But did you know that the gravity experienced by the satellites is four times weaker than on Earth and so time literally passes faster for the satellites in space than it would have had they stayed on Earth. And if your SatNavs did not take this into account (using Einstein's equations of General Relativity), they would become 5 miles more inaccurate every day.
Also, the very first bomb dropped by the Allies on Berlin in World War II killed the only elephant in the Berlin Zoo.
