"... "Ask yourself: what open source software exists that solves a big problem in a large market?" ... then host it and provide it as a service ..." I'd agree

"... "Ask yourself: what open source software exists that solves a big problem in a large market?" ... then host it and provide it as a service ..." I'd agree with that one. Free software allows you to take an individual copy then run it yourself or even run a company. It's not as if Free or Open source software has to serve the market any more than that.