Elegant as Clockwork template for Apple Pages
Pages is a quite nice word processor even though has several quite stupid anti features (such as the page being stuck to the top-left corner). Nevertheless it is currently my tool of choice when I need a document with more than headers, lists and bold text, for which I would of course choose markdown. I have created my own default template, which you can of course download right here. In the zip file you will also find a document explaining all of the features of this template. You can see how it compares to the default style on this image:
Download the zip package containing the theme here:
To install it, put it into ~/Library/Application Support/iWork/Pages/Templates/My Templates