I've used the windscreen washer trick.
The slamming on the breaks thing here will actually land you a ticket, working tail lights or not. They class it as "contributing to an accident", it also means you can't get insurance excess covered by the tailgater.
Good story from this morning though, coming to work I was cruising @ 120km/h (limit is 100km/h) into work, some guy in a white toyota van comes up behind me, ~ 130-140km/h, does the tail gate thing, I get out of his way and he disappears up ahead. I think to myself "I bet you don't have a radar detector or laser jammer".
Sure enough I round a corner about 1 km behind him to see a cop pulling out ahead of me, lights going, and grabs the guy. Probably laser'd him cos I didn't pick anything up on the radar detector and he was in a spot they usually like to laser from.
Very satisfying