Nowadays with more and more IPython notebook files (*.ipynb) around, it is very disturbing every time when I want to peek at some notebook I have to open a server for it, and ca
Intellij IDEA (which is also available as free open-source community edition) can render ipynb files as well. In fact it also allows to author notebooks, so it's not just a viewer.
It can be used via file type associations or via the command line launcher (e.g. idea foo.pynb).