This is a completely dark theme for the Jupyter Notebook interface. Jupyter includes iPython 4 as its default kernel (which, confusingly, supports both Python 2.x and 3.x). Since the iPython 3 to 4 transition, it has gained better support for other interpreters like R and Ruby. It is possible to upgrade iPython 2 or 3 to Jupyter + iPython 4.
Source code coloring is based on the Twilight theme for Textmate. Print preview output for notebooks retains a white background with printable foreground colors.
To install this theme, copy or symlink custom.css into ~/.jupyter/custom/ (create that directory if it doesn't exist.) Then, whenever you run jupyter notebook, iruby notebook, etc. it will use this theme.
All components of the notebook UI are themed, including the dialogs and menus. By default, I've hidden the toolbar, but you can reactivate this by commenting out the annotated line in custom.css.
The notebook list is themed as well.
