From "Twenty Things You Didn't Know About Sugar"
9 The artificial sweeteners saccharin and aspartame were found accidentally when lab workers doing research that had nothing to do with sweetening put a bit of the test compounds in their mouths and liked what they tasted.
10 What kind of researcher sticks an experiment in his mouth?
11 At least he had an excuse. The scientists who discovered sucralose (now sold as Splenda) were originally trying to create an insecticide. An assistant thought he had been instructed to “taste” a compound he’d only been asked to “test.”