I've semi-seriously considered getting one of those flashing process lights that you see on industrial equipment and hooking it up to a pi that monitors the power draw through the outlet and lights up whenever it goes high->low.
Oh you can get a zwave or similar power switch that can monitor power usage that does that for you, no custom rpi required. Then you make an automation that sends a push once power is down after an initial increase minimum.
There are also high power zwave switches that should work with driers too.
