Gerry Sussman is truly one of a kind. He designed the Scheme language and Scheme chips, designed professional telescopes and founded the field of synthetic biology. He's a bonded locksmith and an expert watchmaker as well.
Not so incredible; Gerry has always loved physics and in the 80s built a digital orrery in scheme shortly after SCIP was written. I believe this book had its earliest inklings in that work.
Around March 2019, I walked up to Gerry at the end of a class he taught (I was sitting in) and he mentioned that he was actually a physics major at MIT when he was an undergrad (in addition to math) but was one course short. The course he was missing? Junior lab (now 8.13 / 8.14)