Get your sonar on, without the nuclear option.
What do dolphins, Tom Clancy novels, and your laptop have in common? They can all make good use of sonar!
Non-coders, you can stop watching at 1:20. For everyone else, you can rig your computer to automatically sleep by using your computer's mic and speakers to detect via echolocation when you walk away. (via Lifehacker)
SCIENCE CIRCLE 