Just saw this

[jerrymrc]

I used to build fake ones for training. Back about 2000 I went as the Unibomber and had made one. A few years later someone remembered my little fun and so I made a few. I just wired them up so if you cut the right wire it stayed green. Cut the wrong one and a red led lit. Also made a few with a 555 timer and circuit so the light on the button would flash faster. That one almost got me in trouble as I had two buttons. I fired it up, placed it on the bosses desk and said as I walked out, "Now which one turns it off?" My favorite thing to start with was a Mac 8 EKG battery pack. Edit to add that this was all done for DOD/Army training on an installation.