I've just got back from Marmaris in Turkey. Whilst snorkeling, I saw an interesting fish - about eight inches long, with what appeared to be a long fin extending from just behind the head to 3/4 the way along the body. Could this have been a flying fish, or as one of my friends suggested, a trigger fish?
The fin or spine was connected just behind the head, and then continued unattached along the body. Sounds like it was a flying fish indeed, which is very cool!
It swam away before I could eat it.