[Queen_of_Mascot]

At our school, we have one of the computer labs set up so only the front of the tower is accessible. While it isn't locked down, with the setup, it takes a good amount of time and fidgeting to take away the cables, since its put in a recessed shelf of sorts, with the monitor set up behind glass under the desk... erm...

I really need a pic to show you, but I think the system isn't custom-made, so you could order it en masse. I'll try to get back to you with a pic once the school year starts.

The lockdowns we use at our school leave the front exposed, while protecting the back too, but they're for much older computers... I'm not sure if they make lockdowns like that for newer computers. They're the white metal ones with the two locks on the front, that I'm referring to, with the odd circular keys.