BT Watcher

Detect when you leave office and automatically lock computer. Program determines if you are present by testing connection with your bluetooth enabled mobile phone. Immediately after installation you can assign your mobile with BT Watcher, and you can forget about locking screen: BT Watcher will do it every time you will leave the computer's nearby. To get more security, you can protect BT Watcher by password, if set, password will be needed to deactivate BT Watcher. BT Watcher show only small icon in system tray and balloons about important events, so is almost invisible in work.
You can define time after which BT Watcher will show warning message, and separately time after BT Watcher will lock your screen. You can define custom command to execute to, such command could be executed separately from locking screen.
Program is best for business persons, or professionals whose travel a lot with notebook BT Watcher can also shutdown your computer, or start other task defined by you.