I've worked with 3 of them at different times in my career. They could do as much work as an entire team. One of the I worked with really well, I would feed him ideas and he would code the most incredible things, like parsers using ANTLR. He unfortunately committed suicide. Another one was the CTO of a startup, this brilliant Russian guy that literally did everything to keep the company running. The last one is ex-military that can single-handedly code extremely large systems but was kind of hard to work with because he was so much faster than me. I basically left him alone and fed on whatever breadcrumbs he wasn't interested in, and we co-existed well together.