Now I've heard them re-use the “Terror Dog” growls in other movies, and T.V. shows, but NEVER Slimer's grunts and groans from GB1 in anything else…
Twenty years ago, before “LaRonde” became “SixFlags” at Montreal, there was an attraction called the “haunted castle” (I'm not sure about the name). There was a tower on its left, with a mechanical demon that was exiting of its window. I was always looking at its details while wondering why they put that there, in the middle of this joyful place. But the most curious thing that I was trying to understand was: how can he scream like Slimer when he's not even him?! Coming out of the window, he screamed like him when he was attacking Venkman. When he returned in it, he screamed like Slimer when he ran away from Ray. Then the thought came that they were not good enough to make their own scream so they took one from Ghostbusters :p (^_^)