Compare two images together inline to see how closely they match. This is very useful is you are working to a set of designs, you can take a screenshot from the device and overlay it ontop of the design and check how close you are.
You take two screen shots like
Open them with imgreveal and you will see just one image. You can then click anywhere on the image to reveal more or less of the top image.
This is great to get font sizes correct, line up elements and check sizes when working with mockups.
The application is written in python using the Qt PySide bindings, these proved to be very good for creating a quick GUI based application in Qt.
The source for this application is available on github https://github.com/bobthekingofegypt/imgreveal