As for me, it would have to be the Guy Revan incident on EI, (as already mentioned) 7K in bonds, gone completely. Hilarious... to everyone except him. I believe I heard that he RP'ed it as walking around Ibladesh City ripping up the bonds and throwing them at peasants or something.
Or I could reach wwwaaaay back to Minas Ithil's golden age and say Raziel's ICBMs. Those where the good ole days...
Vellos, I honestly thought that I would log back in and find that Paul had gotten bolted for that. If I remember correctly, I didn't log in for about... 24 hours because I didn't want to know how it turned out.
...as a study on how people react to displays of power, I only had to give out... one fine? Maybe two? We're not talking about a small Avamarian population here, nearly 80% of that realm joined Oligarch - and they TALKED constantly! And yet, one threat from the "law" and they all followed. Displays of power, no matter how they are disguised, will be followed by 90% of the population - just because.
So Rulers, if you want to shake up your realm, do it. Literally, figuratively, whatever. Just do whatever you want and no one will really stand against you. After all, rebelling is hard work.