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This all closely relates with what you do with the guy from "Microsoft support" who wants to help you get the bugs out of your computer.

If you are in a hurry, then either a barrage of highly descriptive personality assessment (generally involving deep profanity and description of close relatives) or a howler (if you have one handy) must suffice, but given a little time, there are more creative approaches.

(Previous thread on this subject somewhere, almost certainly plural.)

Now there's a project - do you need an Arduino to construct a line-connected howler? Probably not - a 555 is a good start.