Saw this first hand at one of the companies I worked at. One developer had built the ENTIRE company backend on his own. A system that every member of staff used on a daily basis to get their work done and that kept the whole $40m+ a year operation going. I'm not 100% sure what he was earning, but I doubt it was more than $80k a year.

Goes to show that creation of wealth and accumulation of wealth are not the same thing.