WordPress › Markdown on Save « WordPress Plugins.
I’ve been a fan of Markdown for quite some time, but never took the jump to fully implementing it on any of my sites. I always had this nagging issue of ‘what if I want to switch back?’ and I simply continued writing my posts in TextMate and logging into WordPress for the 30 seconds it takes to copy and paste my article and hit the Publish button.
Enter Markdown on Save. This thing is perfect. It’ll give you a meta box with a checkbox dictating whether or not the current post is formatted in Markdown, but the better part here is that the Markdown version of your post is stored separately from the HTML version. Why didn’t I think of that?!
If at some point down the line you find yourself hating all things Markdown, you can deactivate the plugin, and your HTML-ified content is as though you wrote it that way. Big thanks to Mark Jaquith for this one.