Today we got our dishwasher fixed under warranty. To diagnose it, the tech stuck a photosensor+magnet onto the front panel over the green status LED and started reading diagnostics. It turns out the status LED is actually a serial port*, and it's continually transmitting status.

I can think of so many gadgets that could and should use this trick...

*It's probably something other than regular serial -- a UART's TX would flicker. I don't know any details.

#HidingInPlainSight