StrapDown.js is an awesome tool to write nice-looking webpages in pure Markdown, with no server side compilation (as the page you are reading).
More details on http://lbesson.bitbucket.org/md/index.html, with example and all.
This project is released under the GPLv3 license, for more details, take a look at the LICENSE file in the source.
Basically, that allow you to use all or part of the project for you own business.