A totally weird new way to unlock your computer

Knock is a new app that activates your computer with a simple knuckle-tap to your phone screen. Download both its iOS and desktop apps ($2.99 and free, respectively), and once you've activated Bluetooth for both devices, it'll walk you through the foolproof setup, training your phone to enter your desktop/laptop password from afar whenever you knock on the screen. If the creeps in your office weren't reason enough to set your computer to autolock when you step away, this little trick just might.