But having had your bright, fresh, original idea, the really hard part is turning it into a successful product. That's what takes all the sweat.

I'd work eighteen-hour stretches and fall asleep in my clothes. Then I'd wake up in the middle of the night, brew a pot of tea, and start work again. I was tired, but work had become pure enjoyment.

That was the Alka-Seltzer moment, the moment when the tablet hits the water and begins to fizz.

The notion that inventors are anorak-wearing crackpots with glasses held together with Sellotape is beguiling but wrong.

I was on automatic pilot; ideas for gadgets kept coming, fed by a force of energy flowing through me and around me.

A good idea turns every cog in your mind, making you scared of bed in case the whole machine grinds to a halt.

Do what gives you a buzz.