Monitor your home wherever you are and whenever you need with the small-but-mighty Nest Cam. Its 24/7 live stream and 130-degree vision wide-angle view (with zoom!) are the technological equivalent of having eyes in the back of your head. You can even use it to listen and talk into the room with whoever might be home—like the kids who just got back from school, or the dog that's disobediently sitting on the couch. When you aren't tuned in, Nest's app will ping you to let you know of any unusual activity. Available on Amazon; $199.