Little clicky switches are standard input "buttons" on electronic projects. These work best in a PCB but can be used on a solderless breadboard. The pins are normally open (disconnected) and when the button is pressed, they are momentarily closed. They...

IR sensor tuned to 38KHz, perfect for receiving commands from a TV remote control. Runs at 3V to 5V, so it's great for any microcontroller. To use, connect pin 3 (all the way to the right) to 5V power, pin 2 (middle) to ground, and listen on pin 1. It...