Any idea what could have caused it? I drive a '94 Toyota Corolla, it seemed to be coming from the front part of the car, where the engine and all that is, it lasted for maybe 5-10 seconds, and as far as I can recall, the car behaved completely normally aside from making that bizarre sound. My car has started shaking a bit whenever I go over 50mph (it used to just shake when I went over 60), so, uh..any idea why it's doing that, and could it be related to the dog thing?
Of course there's always the possibility that a dog latched onto the underside of my car and got excited whenever I really started to gain some speed, then snuck off after I parked, but I'll let TQC be the judge of that (and soon, a mechanic!).