I've always found the concept of wearing a shark-fin shaped dorsal appenditure and swimming around the sea in public beaches to be quite a hoot (inspired by homer simpson of course).
Problem with that however, is that you'd run out of air and have to re-surface for a breather. So why not incorporate a snorkel like tube thats cleverly concealed in the fin, and runs up the back of the wanna-be shark, around the neck, and into the mouth. fun
Mind you, it's not too uncommon for coastguard and lifeguard partols to harpoon dangerously close, erraticly behaved sharks.-- shinobi, Apr 20 2006 (?) richy www.funtime.comrichy [richy99, Dec 28 2007] I saw a cartoon where such a joker met his demise when he unwittingly approached a shark carrying a human-shaped dorsal fin.-- phundug, Apr 20 2006 My freediving boat captain has experimented with a variety of alternative snorkels. It always comes down to simplest is easiest to breath through.
Which means no excessive length, no valves, etc.-- normzone, Apr 20 2006 Yeah, I believe they used this in a Jaws movie, however the snorkel was on the outside. Kudos to you for thinking of a more realistic fin.-- sab8823, Apr 22 2006 random, halfbakery