A while back Devan (VE7LSE) from Nanaimo mentioned this page to get in touch with BC hydro to report RFI from their power distribution system. Apparently, RFI is something BC Hydro wants to know about because it's often a symptom of faulty equipment that cost them power losses (and therefore $$).

QRZNow published an article about the MFJ-5008, an ultrasonic receiver with parabolic dish that's “tuned to the ultrasonic range of 40 KHz allowing you to hear the ultrasonic noise generated by the corona discharge and arcing connections that generate the power line static on your radio.” If anyone gets one, please report back on its efficacy.

This ARRL Power-Line Noise FAQ is also really informative.