Rick, do you have any idea how much current that relay draws when it's in its quiescent (off) state? Could your box last for, say, 6 months as long as the buttons weren't pushed?
Also, you mentioned the ability to use the button as both a power switch and an input to the Arduino, but I gather the circuit you share above doesn't show the latter? If you wanted to add this, I guess you'd just connect the relay pin 1 line (from the button) to an Arduino digital input?
Thanks! This is good stuff.
Mikal