Before making my own switch I used the breadboard to layout a circuit in series and a circuit in parallel to familiarize myself with the equipment. I have never worked with breadboards or an Arduino before, so i was surprised at how easy to understand and user-friendly they were.
I then decided to use the closing motion of my laptop to act as a switch for my circuit, so that when it is closed, an LED will light up. Most of the time I’m up much later than my roommate working on my laptop after she has already turned out the lights, and by having the closing of my laptop trigger an LED, I can avoid being stuck in the dark for the interval between closing my laptop and groping around for my phone (presuming I don’t have the foresight to grab my phone before I close my laptop, which, unfortunately, I don’t).
To create my laptop switch, I set up an LED in series on my breadboard and connected it to my Arduino as a power source. I then attached one wire running from power and one running to ground to the bottom edge of my laptop so that they weren’t touching. To create the actual switch, I secured a small wire to the top of my laptop so that when the laptop is shut, it will touch either end of the wires, completing the circuit and lighting the LED.