I have used git without a central server many, many times. Passing bundles by email or USB sticks, and pushing and pulling between workspaces. At work, it is be

I have used git without a central server many, many times. Passing bundles by email or USB sticks, and pushing and pulling between workspaces. At work, it is because we have often have different networks, isolated for security reasons. For personal use, I don't really have a central server. I may use GitHub, because it offers free hosting and serves as a backup, but it isn't central in the sense that it is not always the git-remote "origin". It may not be the most typical workflow, and it requires some getting used to but it is 100% usable. In fact, I am not aware of a "central server" for the Linux kernel. For all I know, the closest thing to it could be Linus Torvalds's PC.