I've seen a mountain lion exactly one time. I was very young and totally naive to the fact that they are supposed to be extinct on the upper east coast. In fact, I had simply told my father that I saw a 'huge kitty' in our back yard. After about a half-hour of questioning, he told me that it was a mountain lion I had seen and showed me a picture. I confirmed that the cat he showed me was the same kind I had seen in our back yard and he believed me. After that, I was not allowed to venture as far into the woods as normal and had to be indoors by 5pm. I still remember that cat, plain as day. I lived due south of 223 Beecher Lake Road
Livingston Manor, NY 12758 at the intersection of Beecher Lake Rd and Beaverkill Rd. (google map the above ddress).
I may sound like a Bigfoot eye-witness but I saw that cat.
Edit: It sorta reminds me of when I lived in Berlin, Ma and local police swore for half a decade that we didn't have coyotes in town....