I have one bin of parts and connectors labeled “Power”. And then there’s this.
The label or the fancy custom plug job?
The little bin is full of ‘fancy custom plug jobs’ that cross connect everything to everything else power-wise.
Emergency phone charger hacked with alligator leads? Check.
Mintyboost hardwired to a lipo pack? Check.
Six AAAA batteries on an Arduino shield? Check.
The USB-power-to-2.1mm-barrel-connector is among the less controversial items in this little bin. It seems like every little situation has it’s own special power needs which can’t be met by anything normal. The resulting cyberteuthological spawn all wind up here.
Trust me when I say this: you do not want to venture into the dark deep abyss that’s my power bin …
The phrase “217-volt three-phase power” comes to mind.
LOL! It’s a large bin that happens to have glass insulators in it. If that tells you anything.
It tells me that each person has a dark past, and that often the darkness in their past is …due to a major power outage, possibly attributable to them.
Outage or jolt … in my case the latter. 
Ouch.
Glad to have you with us here today.
Hey, I was a dumb 6-yr old who couldn’t get a little DC motor to “go fast” on a battery … seeing how everything gets plugged into the wall … I’ll let you figure out the rest.
Ouch.
And see above re: here today.
At least I got the motor to go really Really REALLY fast for a brief moment.
It’s like I tell people here:
Plug a 12v led into 5v power and only the red lights up, and just faintly at that.
But plug a 5v led into 12v power and the whole thing lights up REALLY BRIGHT!.. once.
It’s been a few decades since I popped a red LED, literally. Connected to a 9V battery, half the LED went flying. It was a scientific experiment, not accident.
Smoke-emitting diodes!
(See also: light-emitting resistors.)
Yah. I’ve killed components, but its been a while since I popped an LED like that!
My buddy’s dad worked at a small electronics shop at the time. We were doing all kinds of “fun” experiments with discarded stuff. I’m still amazed that we didn’t blow ourselves up, or cause serious injuries.
Once you let the ‘Magic Smoke’ out, it’s dead…Forever.