Two entangled particles stay correlated even far apart: measuring one instantly tells you something about the other. Yet you cannot use this to send an instant message. Each result, taken alone, is perfectly random; the correlation only shows up when both lists are compared, which requires an ordinary signal limited by light speed. Relativity survives intact.
Cooled below −183 °C, oxygen turns into a pale blue liquid. Pour it between the poles of a strong magnet and, instead of flowing away, it hangs suspended between them. The reason lies in its unpaired electrons, which respond to the magnetic field. Liquid nitrogen, by contrast, is colourless and pours straight through.
In 2012, Felix Baumgartner jumped from a capsule hanging beneath a balloon, about 39 kilometres up. In that extremely thin air almost nothing slowed him down, and he reached around 1,358 km/h in free fall, or Mach 1.25. He became the first person to exceed the speed of sound with nothing but his own body.