Hardware :: Lock Computer With Flash Drive

I recently got a new Lenovo netbook and I want to make sure that what happened to my last laptop doesn't happen to this thing. I got the idea from some Windows software called Predator, that uses a flash drive to lock a computer. I also know that most Linux distros already have the required components to facilitate this (i.e, they know when you plug in a flash drive). My question is, how do I get my netbook to run scripts or programs when a flash drive is unplugged? This is how I want it to work: The flash drive would be tethered to my wrist with a short strap (or a piece of fishing line, maybe a chain). When someone yanks the netbook away from me (i.e, a thief), they would rip the drive out of the USB port in the process. The netbook, immediately sensing that the drive is no longer plugged in, runs miscellaneous programs or scripts in an attempt to thwart the thief, like activating the screensaver, adding a password to grub, sounding an alarm, and whatever else I want it to do.

I would eventually like to expand this to bluetooth headsets, and other devices that Linux can keep track of. It also has to fit in with my current setup. I installed Xubuntu 9.10 on the netbook and set it up to use an ext3 formatted flash drive as /home. I then installed truecrypt and created two file containers, one for the flash drive (small files, like assignments for college and app config), and one in a hidden directory on the hard drive in the netbook (large files, like my VirtualBox images).This way, the system won't work right without the flash drive, and I can even switch flash drives in the future, when the one I'm currently using dies. Ideally, the system locking program/script would only check for a USB connected device with a special file on it. If I can get this set up, it would be one of the coolest Linux tricks ever pulled with a netbook, and possibly the basis for an awesome new security tool for mobile users.