I found a USB Cellular data adapter in the trash and plugged it in to my MacBook Pro, which instantly shut down. Rebooted, and the USB port did not work. Shut

I found a USB Cellular data adapter in the trash and plugged it in to my MacBook Pro, which instantly shut down. Rebooted, and the USB port did not work. Shut it down and left it for half an hour, and, yay, all working again. Disassembled the adapter. Turned out to be a dummy used for display. No guts, just a steel bar across all four pins of the USB connector. Looked real from the outside. It was a very, very stupid thing to do. Thank-you Apple for putting a self-resetting fuse in my MacBook Pro. Saved my idiot butt.