MarkdownPad http://markdownpad.com/ is neat and does the preview thing, split screening your editing. (requires Microsoft .NET Framework 4 Client Profile, which it comes with and installs if you don't already have it. Windows XP, Vista, 7, and 8.)
Dillinger. It's open source, so you can also run it locally or on your own server. It's also a web-app, so it's cross-platform, too, of course. http://dillinger.io/
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Can anyone recommend a Markdown editor with Markdown code on the left and a preview on the right? OS X or Windows. Doesn't have to be free.
Mou is pretty good (and free)! http://mouapp.com/
MarkdownPad http://markdownpad.com/ is neat and does the preview thing, split screening your editing. (requires Microsoft .NET Framework 4 Client Profile, which it comes with and installs if you don't already have it. Windows XP, Vista, 7, and 8.)
Take a look at my comment above. It does what you want. I am not sure why I was down-voted!
Dillinger. It's open source, so you can also run it locally or on your own server. It's also a web-app, so it's cross-platform, too, of course. http://dillinger.io/
This one is a web-based editor which you can embed wherever you want. It's basically a replacement for WYSIWYGs:
http://epiceditor.com/
http://code52.org/DownmarkerWPF/ does this as well. It's both free and open source.