The standard dark theme from Bforartists also works in Blender.
To install the theme first extract the XML file where you want. Then simply use the install theme button in the user preferences to browse to that directory and to install the theme. The current version is made with Blender 2.76. It can be that it doesn’t work with earlier versions.
Download, 4 Kb: http://www.reinerstilesets.de/blender/bforartists_dark.zip
14.12.2017 – Fixed tab color in the animation editors. Download stays the same.
05.02.2017 – Fixed some more quirks.
17.01.2017 – Fixed some quirks. Black font at black header was not really readable …
Download stays the same.