Growing up in NJ, earthquakes were unheard of. Back when I was a kid in Bergen County I felt one. It was a Saturday morning, and I was at a friend's house after sleeping there the night before. It lasted long enough for us to realize we didn't know what was going on and to run outside of the house and witness everything moving.
I was thinking about the quake lately and finally managed to track down the event. According to the Lamont-Doherty Earth Observatory of Columbia University, the earthquake occured about 6:04am on October 19th, 1985 and was measured at 4.0 on the Richter scale. Its epicenter was in Ardsley, NY. (40.98N, 73.83W), referred to as the "Ardsley Quake".
