But that's just it, I have to find a use for it. It isn't immediately obvious to me. I'm not the typical designer as I don't have clients and my job isn't 100% design but I have been designing everything from packaging, to print advertisements, to websites for ten years. I don't know why I would use this. If I need alternate versions of files I just save them with version numbers. The poor man's version control. But I don't need anything more than that - do other designers?
The power of Github I believe is that it allows programmers to share their work with their colleagues, learn from others, and work together with others.
I like Dribbble because it allows designers to do what they want to do with their colleagues. Show off their work and get inspiration from other designers. To me, Dribbble is the closest thing to a Github for designers.
What's missing from Dribbble is the collaborative part. Coders working with coders, designers with designers. But that's the problem. Coders have to work with other coders all the time it's the nature of the beast. Designers do not in the same way. In my experience.
So if it's not designers with designers then it's designers with coders. And a place for those who (like me) both design and code to both showcase our work and to work together with others. If you could turn this into a Dribbble + Github I think that would be interesting.