Edward Craven Walker, a Royal Air Force pilot in World War II turned nudist filmmaker, came up with the idea for his iconic Lava Lamp while "drunkenly transfixed by a strange gadget at a pub."
On a presumably rainy day in the mid-1950s, Craven Walker paid a visit to Queen’s Head, a small pub southwest of London. When he sat at the bar to order his first pint of Guinness, he noticed something strange perched beside liquor bottles on a shelf.
A glass cocktail shaker full of water and oil blobs sat on a hot plate; upon being heated, the oil would rise to the top of the shaker. When Craven Walker inquired what this strange device was, the barkeep told him it was an egg timer: in just the amount of time it took the oil to rise, an egg could be fully cooked. Years earlier, a regular at the pub, Alfred Dunnett, had built the contraption, Craven Walker was told -- but it was only a one-off, and Dunnett had since passed away.
Determined to pursue the idea further, Craven Walker contacted Dunnett’s widow and purchased the man’s patent for a sum of less than £20 (about $30 USD). For the next decade, between his nudist philandering and cinematic pursuits, Craven Walker set out to craft this rudimentary egg timer into an interior decoration.
Pricenomics has the full story, with lots of cool photos: The Lava Lamp Just Won't Quit