Here is an interesting link for a "capacitive touch" capability to your projects.  I have not trried it yet, but plan to in the next couple of days.  This will work nicely into some of my project ideas.  

https://www.instructables.com/id/Arduino-Capacitive-Sensor-in-Less-Than-2-Minutes/

Capacitive Touch - Only have to touch/hold ONE wire, not create a loop circuit.