Is there any chance that GOG will sell also non-gaming software? So if I write some really good stuff says in C++ is there any chance I can sold it through GOG?

I've thought GOG is only for gaming. Steam on the other hand is experimenting with the selling software idea. But if you have a good program which is picked up by many, you can always self-market it like the guy who created Total Commander.

That's like asking for GameStop to stock kitchen appliances next to their consoles. Usually independent developers sell their software on their own websites, either rolling their own store solution or using a service like Fastspring. There is also the Mac App Store on OS X, and I'm sure the various Linux distributions and Windows have something similar.

I could see GOG releasing some game-related software. The only program that comes to mind is that cartography application that appeared in the forum some months ago. That would make a good bonus freely included with certain older grid-based RPGs.