Not sure if I'd categorize this as "cool" (moreso "annoying"), but last Sun Jan 16 prior to boarding AC901 FLL YYZ, FLL was evacuated and we were all ushered by TSA onto the tarmac through all of the side exit doors. Fire trucks and police vehicles were rushing in from what seemed to be everywhere. We all watched the spectacle in amusement and was finally let back in once TSA officials horded us into one group. Thank goodness we didn't have to go back through security though. Never found out what the issue was though.