WP-Markdown (wp-markdown) free WordPress plugin

This plugin allows you to write posts (of any post type) using the Markdown syntax. The plugin converts the Markdown into HTML prior to saving the post. When editing a post, the plugin converts it back into Markdown syntax.

The plugin also allows you to enable Markdown in comments and bbPress forums. In these instances the plugin adds a toolbar, and preview of the processed Markdown with Prettify syntax highlighter applied (similiar to that used in the Stack Exchange websites such as WordPress Stack Exchange).

WP-Markdown stores the processed HTML, so deactivating the plugin will not affect your posts, comments or bbPress forums.