I have never seen one, despite visiting a lot of places they are rumored to exist.
The really weird thing is that Pravda and the National Enquirer seem to have a monopoly on the only non-zombie reporting. Now that is horrific.
Never saw a vampire either. In Bolivia some believe a mythic gringo roams the mountains at night seeking Indians to press into oil for the machinery. Spooky stuff on those very dark Bolivian nights.
Then of course we have the real monsters. The Golddigger, the Ex, and the Red Headed High Maintenance. Scary stuff. Too scary for the movies.
These creatures cannot be killed with any known conventional weapon. It takes a court order driven through their heart. You may also enter stealth mode by donning a mantle of poverty.
There is also a nest of about five hundred of the most dangerous creatures on earth, they look like normal humans, but seem to live forever. Their name must not be spoken. It is too horrific to even utter.