The Targus Notebook Security Defcon CL Combo Cable Lock is standard issue laptop security at my work. We use this device to ensure that our laptops are secured to our desks while in the office or travelling to other office locations.
The cable lock is a gavlvanized, steele-cut 6.52 ft. grey chain covered in clear plastic vinyl. The width of the chain is about the same width of a pencil. The cable lock easily attaches to my laptop or any other devices like a desktop computer, monitor of even projector. Your device must have a lock slot though. While in the office I just fish the cable through the cable slot in my desk and form a loop. However, there is a base plate with a metal loop that also comes with it that you could attach to a desk that doesn't have a cable slot in it.
There is a keyless combination lock. You can set or change up to 10, 000 different number combinations. I rated the 'Ease of Use' low due to the fact that the keyless lock isn't easy to engage. The cable lock I was issued seemed to be stuck and wouldn't allow me to even set it. I only realized that after I had secured it to my laptop! I had followed the instructions on how to set the inital combination, tried to open it one more time - which worked, but got stuck when I attached to the lock slot on my laptop. They had to call a locksmith in to cut the cable and break the lock off from my laptop. I just couldn't get the darm thing to take the combination I had set so it would come off! You have to set teh numbers, push in the button and turn. For some reason the tumblers just would fall in to place so the lock could open while it was attached to my laptop. That's why this gets 5* for Effectiveness because my laptop was actually locked up and secured.