Available for $29.00 from Aflava.com. At that, perhaps a little pricey, but a complete rewrite of a good product into an even better one. Again, a markdown editor with code folding and snippets. Toggle live preview on and off, word count, spell check, themes. Recommended.

Many thanks for this hint!
Smartdown II looks like a very nice editor developed by a very smart mind who really knows what you need when writing a text. I will test it tomorrow at work first but I am pretty sure I am going to buy it.

Best,
Dominik

I forgot to mention this coupon code: 1BA3F030 and get 20% off until March 31st. I've been playing with it some more and it's very nice. As Dr. Andus once mentioned, there's a trade-off between the power of org-mode and the 5-10 minutes it takes to learn the commands of a good markdown editor with folding. You could do a lot of writing in Smartdown II without having to invest much time in the learning curve.

I am a long time user of Smartdown. The new version works a little bit slower, but the new features are worth it.

With the new Library view, you can easily set up a great plaintext writing environment. I personally use it with Simplenote account and Resophnotes (set to store content in separate txt files) for synchronization.