[MBAtarga]

The wife and I have an understanding when she visits me in the shop building or the garage. She flips the light off/on very quick to get my attention. The light flickering doesn't surprise/scare me - it's a quick blink - then I realize the only reason they would have flickered like that is because she has just dropped in. Of course, this was only arranged after coming close to a heart attack more than once when deep in concentration standing in front of a running table saw.