MDwiki is a CMS/Wiki completely built in HTML5/Javascript and runs 100% on the client. No special software installation or server side processing is required. Just upload the mdwiki.html shipped with MDwiki into the same directory as your markdown files and you are good to go!

Madoko is a fast markdown processor for writing professional articles, books, manuals, webpages and presentations, with a focus on simplicity and plain text readability.

With Madoko you can write complex documents completely in markdown and get beautiful PDF and HTML output.

Raneto is an open source Knowledgebase platform that uses static Markdown files to power your Knowledgebase.

Abricotine is an open-source markdown editor built for desktop.

If you need to convert files from one markup format into another, pandoc is your swiss-army knife. Pandoc can convert documents in markdown, reStructuredText, textile, HTML, DocBook, LaTeX, MediaWiki markup, TWiki markup, OPML, Emacs Org-Mode, Txt2Tags, Microsoft Word docx, LibreOffice ODT, EPUB, or Haddock markup