Years ago I used to maintain a personal wiki. I used the wonderful software Confluence from Atlassian. They have an affordable license for the small user (10 users for 10 bucks) and it's decent software.
I have been wanting to get back to having a private wiki for a while, so I can consolidate documentation for myself. I know how I think and I know how I like things written. The older I get the harder it is for me to remember how I did things.
However I didn't really want to burn up proc cycles and generate heat in my server closet in the house with a heavy wiki. So I had decided that I would just use Bitbucket and manage my documentation in a private repo and just use text files. However once I logged in and started poking around I realized every repository has it's own wiki associated with the repo, and you can actually manage and edit the wiki as it's own git repo.
Well that seemed to me to be the best of all possibilities. It's free, I can use markdown. I can manage it all with git, and I can edit in vim.