Registering whether the mouse has moved so that I can create a screensaver

I’m basically looking to create a screensaver within the flash file i’m using. So if the person doesn’t move the mouse for say a minute, actionscript will detect this and play a movie ( screensaver type one )

It’s within a digital application and the client wants a built in one rather than making a proper one.

Does that make any sense?

Many thanks in advance

Tristan