When I was 7 years old playing SMB3 at a friends house, we somehow came to believe that those flame-tailed flying bombs in world 6 would not only kill you if you let them go off, but they would also disable the NES for 3 whole days. Needless to say, whenever he came on the screen, we went apeshit. His 5 year old brother often started crying.
To this day, I still freak out a little when I see that guy.