Not airliner related this one but as an instructor you get to witness some strange reactions from passengers...
Funniest reaction I've had was on take-off during a trial lesson with the customer's girlfriend in the back of the aircraft spectating. As we took off it became very obvious that perhaps staying on the ground would've been a better move because the thing was bopping all over the bloomin' sky in gusts of wind.
As I battled with the controls and tried my best to give a running commentary on the take off without my voice wobbling in the motion of the aircraft, the girl in the back started laughing hysterically and uncontrollably whilst her boyfriend grabbed my knee...
VFE.