The SkyBell is actually pretty cool. It is a WiFi-enabled doorbell with a camera and microphone. Stick it on the wall next to your front door. When someone pushes the "doorbell" button, you get can talk to them via your smartphone. It also has a motion sensor, so the camera turns on and notifies you if someone is hanging around your front door but has not rung the bell. Which might really be very useful if you live in a neighborhood with some sketchy individuals around (I'm thinking about some friends who live in Manhattan).