Margen
One evening in 1879, the chemist Constantin Fahlberg sat down to dinner at home in Baltimore and found his bread unbelievably sweet. It was not the bread: it was his hands. He had spent the day at Johns Hopkins University working with coal-tar derivatives and had not washed them.
He rushed back to the laboratory and, with more enthusiasm than caution, tasted his way beaker by beaker through everything on his bench until he found the sweet compound. He named it saccharin: hundreds of times sweeter than sugar, with no calories at all.
In 1884 he patented it alone and grew rich, never mentioning Ira Remsen, the head of the laboratory, who never forgave him. Chemistry gave the world its first artificial sweetener thanks to two things: a stroke of luck and a pair of unwashed hands.