scripted alarm

Here's the scenario:
I work in a contact management company that hires typically young and aggravating staff to answer phones for our clients. We have a 600 seat call centre and the theft of mice and keyboards is astounding and expensive. What I want to do is figure out some sort of script or very simple program that will continuously monitor the ps2 ports and raise merry hell through the PC speaker if anything is interferred with. Ideas?