Another new homebrew accelerator?

[Fats]

Looks more like open source rather than a commercial product...

FYI, open source is not the opposite of commercial, think Arduino...

[Fats]

Last I heard of, they were at each other's throats in the courts.

You are a little bit behind, and even if not it still shows that open source hardware can be sold commercially.

[Fats]

Some are, in vast numbers. The teeny, tiny, minority of successful designs.

Nothing different from the proprietary projects that never reach commercial introduction let alone success. Advantage with github is that attempts are documented and can be build upon.

I'd rather talk about hobby projects as opposite of commercial projects, and hobby projects don't necessarily have to be open source either.