I wrote a quick wrapper script for converting local Markdown files or raw text to HTML using Github Flavored Markdown. It uses the Github API, so there are no local dependencies (other than the json gem, see below). It just requires an Internet connection. Syntax highlighting and Github stylesheets are included in the output. Any syntax recognized by Github is converted, including line breaks and fenced code.
This is a companion discussion topic for the original entry at https://brettterpstra.com/2012/09/16/easy-command-line-github-flavored-markdown