From memory palaces filled with imaginary furniture to synesthetes who see numbers as colors, these mathematical obsessives have dedicated years to memorizing a number that never ends. We're counting down seven people who've turned 3.14159... into their entire personality, including the retired Japanese engineer who holds the record at over 111,000 digits.

In 1961, a former monk made a vow to God and began building a cathedral with his bare hands—no architects, no permits, no construction experience. For over 40 years, Justo Gallego worked alone in rural Spain, turning trash into towers and creating one of the most spectacular examples of outsider architecture the world has ever seen.

In 1637, single tulip bulbs sold for more than houses. In 1999, divorced couples fought over Beanie Babies in court. We're diving into two of history's most absurd collecting manias, separated by centuries but united by one thing: people who convinced themselves that flowers and stuffed toys were worth more than gold.

Some people jog. Some people power walk. And then there are those who've committed their entire existence to moving through life in reverse. Today we're counting down five individuals who turned walking backwards from a quirky hobby into an all-consuming way of life—including one man who hasn't faced forward in over 40 years.

Between 1978 and 1980, a man nicknamed 'Monsieur Mangetout' literally ate a Cessna 150 aircraft—piece by piece, bite by bite. We're diving deep into the bizarre true story of Michel Lotito, his iron-lined stomach, and the psychological and physiological mystery of how someone becomes fixated on eating the inedible.