I was on the ICW in NC when I was struck while at anchor. Blew the mastead light and VHF aerial off the masthead and burned out some random electronics below decks. However there was another effect which I did not find out about till I left the anchorage. My steel boat was now a strong magnet and my compass read due east regardless of heading.
Took a very kind naval compass adjustor a day to drive out the "Bad Spirits".