Fun:Four

4 comes after three, and before six, but five comes first. In this way, these numbers form what is known by mathematicians as the first ordinal circle-jerk.

In the traditional incomprehensible Roman method of writing numbers, four is inscribed thus: IV, which is only useful if you need a quick rush from your drugs.

If you hear someone yell "4!", it means "duck!": it is not much clearer than "heads up!", which means "heads down!"

FOUR is PURPLE.

Or YELLOW depending on your SYNESTHESIA.

or GREEN

4 is also the number of double martinis it takes before the slob you're sitting next to at the bar actually starts to look halfway decent.

In many Asian countries, the word for 4 is a homophone with the word for death, or an omen of death. As such, buildings in China and some parts of Japan do not have a 4th floor, in the same way that Anglophone buildings have no 13th floor.