Ok, this time was more fun with soldering iron!
I have it resting on a little metal stand for maybe 2 hours (while fitting caps and resistors and all that nice stuff on my Learn To Solder and Build a Flashing Eurpoean Siren kit)
So I take it off the stand and put it on a table, and unplug it. I plug in the batteries and get my eardrums hurt by loud siren. I turn down the voleume. Then I see the stand. I grab the metal part and pick it up. It's bee resting under the tip of the soldering iron for two hours, very hot. My hand still hurts.
I do way too many stupid things