Mathematics Magazine 77,1 (Feb. 2004) contains an article about the logician Emil Post, who apparently discovered unsolvability and incompleteness prior to Goedel using a diagonalization argument. But I was more intrigued by the fact that he was apparently bipolar, and was also aware of his condition. His approach to his disease: work on two different problems simultaneously, and stop working on the one making the most progress, so as not to trigger the manic phase. Presumably, if he started getting too depressed on the other problem, he would return to the first problem. A very elegant solution to his problem! Unfortunately, this algorithm didn't always work, and he therefore underwent electric shock therapy. Interestingly, Post also worked later with recursively enumerable sets (which are most interesting when their complement isn't). Many of the arguments involve timesharing a machine to work on a problem and its complement simultaneously -- something Post had much practise at.