I saw a real mermaid. We were finishing up a dive, were at about 40 ft. I looked up and thought at first it was an eagle ray. Then I realized that what I was seeing was a mermaid -- a woman with long flowing hair, and the body of a fish. I thought I was narced. She came down, blew me a kiss, and then returned to the surface.
I didn't realize mermaids were surface breathers but I guess since they are marine mammals it makes sense! Tee hee.