Okay, so I've been wondering this for some time now. I did an initial google search but found nothing:
besides windows, unix/linux based OS, and mac OS, what operating systems are available if any?
Yeah but that is a lot of work and even then he will need some code to baise it off of, like Linux kernal. Creating some new form of code would take a high level of code and take forever for one person, but I guess that depends on what he design's it for.