LiveScience taught me that several popular myths are completely made-up.  I'm most amazed by these false myths: 

1.  The Great Wall of China is the only man-made structure visible from space.  (False.  There are others.)
2.  Draining water forms a backwards funnel in the Southern Hemisphere due to the Earth's rotation.  (False.  Funnels traveling in both directions can be formed in either hemisphere.  It's based on the shape of the sink/toilet and how the water is poured.)
3.  Lightning never strikes the same place twice.  (False.  It definitely does.  Think lightning rods.)
4.  There is no gravity in space.  (False.  Astronauts are traveling tangent to the earth at a speed that's fast enough to keep them from being pulled in by the Earth's gravitational pull.)
5.  Hair and fingernails continue to grow after death.  (False.  Dead bodies dehydrate so much that it causes the skin to retract, which in turn exposes more hair and nail.) #technology