[amorphous]

Any boat of 50+ hp with the right prop pitch would work great for this. The snorkerling dive boats already in use in most vacation hotspots might even be suitable with a prop change.

I think you're going to be suprized how well this takes off. Mark my words, you're going to see people making vacation plans based on the ability of being able to do this.

And who wouldn't want his/her very own autograhped SMORGASboard/SEALboard by the famous author Travis McGee? :-)

[Travis McGee]

You would be surprised how many folks are too afraid of sharks to try it. But a lot would, I guess.