The number 3 has a lot of magickal power for performing arcane rituals, which is why all the equipment at electrical substations is in groups of three.
#TRUEFACT: While sweating cools you down, that wasn't it's original purpose. Sweating was originally a form of the body crying from being unhappy at being made to do crappy things (exposed to heat, working out, the flu). That it cools down the body is a complete coincidence.