Those things you see in your eyes when you stare into space are called Mouches Voltanes, which are also broadly referenced to as Floaters.
9
You can start a fire with ice.
367
Your fingernails grow faster in summer.
744
Fine-grained volcanic ash can be found as an ingredient in some toothpastes.
55
You can hear the blood flowing through your ears if you find a quiet place and cover them tightly.
17
Oak trees can live 200 or more years.
61