User Interface Prototyping with Powerpoint

In the hunt for improving my development methodologies and techniques I recently came across on the concept of using Powerpoint for prototyping the user interface of the application that's yet to be developed. It is quite an interesting concept, apart from getting a look into the idea Long Zheng has provided a template package in  Powerpoint which can be used for designing such prototypes.

I am already loving this idea and planning to use from the current development cycle.