There was this day when I forgot to turn off the lights in my living room before heading out, and as I remembered it once I was outside, I wanted an easy way to switch it off. Because this was five years ago and because smart home systems weren't that popular and common, I wanted to solve this issue by myself using my electronics and programming knowledge.
With the help of an Arduino and a simple LED light to test out the entire project with an Ethernet Shield to connect to the Internet, I used HTTP GET requests to effectively turn off and on the LED from anywhere and at anytime by managing the flow of data using an SQL database and a PHP backend. Check out how it works here!