Whenever a valid key is swiped, the Arduino triggers a relay which can then be used to control just about anything. In this case, [Jason] plans to use it to control his garage door. The system ...

Over on Adafruit, they show you how to build your own that hooks into IFTTT so you can be alerted any way you like when the door opens. The system here uses a cheap Arduino board, a few sensors ...

If you've ever wanted a way to monitor your doorbell from anywhere—complete with video and audio—Instructables user macgeek shows off how to build a system ... person at the door so you ...