The Eureka Moments of the world’s greatest entrepreneurs.

Every entrepreneur goes through a phase when they did not know what to do. Then the magic happened. About 2200 years ago Archimedes stepped into his bath and exclaimed, "Eureka!" - 'I found it.' At that moment he found a solution to a problem he had been pondering for ages.

It was a moment of sudden discovery. The eureka effect. A moment of deep insight. It's an epiphany which translates as 'striking appearance.' At that moment a previously unsolvable problem becomes suddenly clear and obvious.

But what brings the eureka moment?

· Inconvenience : GoPro founder who struggled to take a picture of himself while surfing.

· Limited resources: Ikea founder could not fit a table in his small car, so he thought to take off the legs.

· Pain and tragedy. Samuel Morse received a letter about his wife's illness after she was already buried.

The eureka moment comes at different ages. Here are a few examples.

· Caresse Crosby, inventor of bra - could not fit her bust into a corset

· Steve Jobs, Apple founder - wanted a computer interface as pretty as the calligraphy on his college campus posters

· Bill Gates, Microsoft founder - realized he needed to sell his product before he made it

· Ingvar Kampard, Ikea founder - couldn't fit a table in his car so he took the legs off

· Brad Pitt, actor - saw that graduating matters less than being an actor (2 weeks before graduation)

· Ben Silbermann, Pinterest founder - made 50 versions of the same picture grid

· Nick Woodman, GoPro founder - went surfing and could not take pictures of himself

· Brian Chesky, Airbnb founder - rented his air mattress and made cash

· Sara Blakely, Spanx founder - while selling fax machines discovered slimming underwear

· Samuel Morse, telegraph inventor - found his wife dead because her letter reached him too late

· Jan Koum, WhatsApp founder - could not afford to call his father in Ukraine

· Dietrich Mateschitz, RedBull founder - tried a local drink in Thailand to help with jetlag

· Donald Fisher, Gap founder - could not find a store selling jeans that fit well

· Chip Wilson, Lululemon founder - noticed many women do yoga, but have no special pants to wear

· Momofuku Ando, instant noodle inventor - saw people lining up for soup on a cold day