Developers: OS X Progress bar customisation

Hello all, first post in this forum.

I have a question for developers:

Is it possible to create a OS X application that once installed customises the standard progress bar? 

For example, instead of having the horizontal blue (or grey) progress bar, having a interactive progress bar. Instead of just waiting for the progress bar to tick along, you could perhaps pass the time by playing a simple game like pong or something. So every time you wait for a program to process something large, the game would pop up. 

Is this possible? And could it be made simple for the user to install?

Thanks for your time! 

Cheers