Physical Controllers
Hand holding sensor
Measure the voltage - could be a chain of humans that hold hands, Arduino measure the voltage and smoothes it out with a capacitor. The LED is just to show the difference in voltage:
The Arduino connects to 5Volts, Ground and Analog 0
The Breadboard, purple wires are for holding in your hands. Capacitor to smooth out the voltage.
The code
RFID Tag Reader
Can be used to read RFID Cards/ or write to them. Uses a ~3 Dollar RFID Reader (RC522) Worked best with Arduino Uno.
SEEDUINO XIAO
A super small Arduino/Micropython device. About 15 Euros.
Connecting it to Arduino IDE: https://wiki.seeedstudio.com/Seeed_Arduino_Boards/