DocuMaker is a free asset that will help you create simple HTML documentation from your C# classes. I created it recently to assist me in generating said documentation for my other assets on the Asset Store and decided that it would be a nice simple asset to release to the store for free.
I hope that it will help a few people out there who need to create web documentation for their work. I personally had a shot at some of the other things already available but found them frustratingly user unfriendly and opaque. In less time I bashed this out to the simple specifications I had. The HTML it produces is very open to applying your own stylesheet and the code is all open source (obviously!)