powdiff
Visually diff your production environment and your local Pow server
Usage
Requires PhantomJS and ImageMagick.
$ brew install phantomjs imagemagick
This will render a diff between http://www.example.dev/ and https://www.example.com/.
$ ./powdiff http://www.example.dev/
If you find this useful, I may also suggest a bookmarklet I created for switching between Pow and Production: https://gist.github.com/jelder/7377297