When we see someone giving his PC a rap, we immediately think he either needs a new computer or he needs to enroll in an anger management class. Now there's a third possibility. He could be locking his screen or telling his PC to play the next track on his mp3 player.

The knocking commands are made possible by a Linux program called knockAge. In 2003, IBM rolled out Lenovo, the laptop formerly known as ThinkPad, equipped with integrated accelerometers. The accelerometer was originally designed to protect the HD in case of an accidental collision with the floor. This is where some talented hackers came in. They developed modules for the Linux kernel to take advantage of these sensors.

Using an updated Linux kernel with the Hard Drive Active Protection System (HDAPS) driver and knockAge, you can generate knock codes that will run commands such as screen locking/unlocking, on-screen display orientation, desktop switching, game control and real-time 3D models of the tilt of the laptop. The possibilities are endless.

We prefer to use the keys but hey different strokes for different folks. Check out the video to see knockAge in action. If you want to know how you can knock up your Lenovo you can see the different command codes in the full article.