Way of changing icons easier?

I am wondering if there is an application that allows you to change application icons. I know how to change the icon, but the process is long and slow, and if i want to change the icon from its original image to something new, but than revert to the original icon later on, it takes a very long time to do.

Im wondering if theres an app that allows you to see all your applications and easily change their icons.

Hopefully! If not i can see this being a fun project for me to work on, but odds are itll never get started...