BtProx Locks Your Workstation with Your Cell Phone

Lifehacker:

“Windows only: Free, open source application BtProx locks your
Windows computer whenever your cell phone or other Bluetooth device is
out of range. Similar to previously mentioned Blue Lock,
BtProx includes a more advanced feature set, allowing you to set a
timeout before it locks your PC and run a program when your device is
out of range. I had trouble using it with my iPhone, so if you give it
a go, let’s hear how it works for you in the comments. Again, it’s
still not as cool or impressive as the Mac alternatives, but it seems to be taking things in the right direction. BtProx is free, Windows only.”

BtProx [SourceForge]