Okay, so nothing like shark baiting involving great whites off the coast of australia, but pretty cool all the same.
http://www.underwaterworld.com.sg/ad...divesharks.htm
Very tranquil, although you spend more time waving at the people going through the tunnel than looking at the sharks and fish. Incredible though, and only about S$95 (£30) for 90 mins (30 mins underwater)....
Incredible great beasts down there, Dugongs, massive rays, sharks (nothing longer than 2 meters though), and some bloody ugly fish like a giant angel fish with colligen lips.
They're pretty easy going about grabbing hold of the big fish and letting you hold them, and most of the fish in their are incredibly tame.
If you're in this neck of the woods, I heartily recommend it. You don't have to be a certified diver to do it, and for what you get it's cheap as chips.