A portable open source freeware application that locks a PC via USB is a beta worth investigating.
Lock Down a PC with Raptor Freeware
by Jim Hillier for Daves Computer Tips
I can think of several scenarios where the ability to lock down a PC may be beneficial, even outside of a work environment. For older children with younger siblings perhaps, or parents with children, or young adults sharing accommodation.
It’s quite easy to prevent access to a password protected PC via the Windows native lock feature of course but that is not always the most convenient or secure solution. How about securely locking down a PC simply by removing a USB flash drive? That’s exactly what these two free products promise to do.
USB Raptor is a portable open source freeware available through the SourceForge repository – it should be noted that USB Raptor is still in Beta stage.
Download USB Raptor here: http://sourceforge.net/projects/usbraptor/?source=typ_redirect
Access a FAQ page here: http://sourceforge.net/p/usbraptor/wiki/FAQ/
Here is the developer’s description:
USB Raptor can lock the system once a specific USB drive is removed from the computer and unlock when the drive is plugged in again to any USB port.
The utility checks constantly the USB drives for the presence of a specific unlock file with encrypted content. If this specific file is found the computer stays unlocked otherwise the computer locks.
To release the system lock user must plug the USB with the file in any USB port.
USB Raptor is a 10.7MB zip download. Running the software is a simple matter of extracting the files and double clicking the extracted executable, no installation required – (scans 100% clean through Virus Total). The program opens to a simple configuration window by default, involving just three basic steps – set a password, select connected USB flash drive, create a key file: