Leaving your computer unlocked is not a great idea, especially if you store sensitive files on it. Some of us simply forget to lock our computer when we get distracted. Sesame can help. It is a wireless lock for Macs that locks your computer when you are out of range. Everything happens automatically to make it more convenient for users.
Here is how Sesame works: All you have to do is put it in your pocket and go about doing your work normally. When you are far enough from your Mac for Sesame to be out of range, your Mac gets locked. Upon your return, the companion app for Sesame unlocks your computer. Users can decide how to unlock their Mac. Sesame also offers auto-mute and auto-pause for iTunes. It uses Bluetooth 4.0, so it is not a power hog. Sesame can run on a coin cell battery for months. Sesame even offers 2-factor authentication.
This product looks quite promising for Mac owners. It is not too expensive either.