My cat is named Ripley because she was found on the street with a bad virus infection. A friend saw her and thought she looked like she had an alien inside her, so the name from the movie instantly stuck.
My cat is named Ripley after the Broadway Actress Alice Ripley.
We named our cat Ripley because The Talented Mr Ripley is our favorite movie. Also after Signorney Weaver's fearless character in Alien.
I have named my cat Ripley after Ellen Ripley, from the movie Alien.