A wiki seems like a good idea here, but if that isn't a good fit, you might like to consider using Sphinx (or similar) with ReStructured Text.
Although this, too, would be a "little programming project", it would provide you with HTML as output while keeping the diffs pretty and readable. Setting it up would, I believe, be less of an effort than for LaTeX; the learning curve would be quite a lot smaller; and if you need LaTeX and PDFs in the future, it's there waiting for you.
