One of the best programmers I've ever met.
He couldn't do complex big-O analysis because he never learned it having started to work straight out of high school, but other than that, his code was meticulous, he gave excellent code reviews, and just had this natural understanding of technology and how to program. Probably the best programmer on our team, much better than me and I often sought out his opinion on things, even though I could have been his dad. I always learned things every time I talked to him.
He is a multi-millionaire now, and still works as a programmer but does it for fun.