A few weeks ago we organised a public speaking workshop for the whole of Clearleft. A lovely chap called "Alex Marshall":http://www.alexmarshall.com/ hosted the workshop, and asked us all to give a 5 minute presentation to the rest of the team. Each session was video recorded and then played back to help us see what we're doing well and what we're doing badly.
I've been a dive instructor for several years, and have worked as a safety diver on shark feeds in the Great Barrier Reef. I've dived with all sorts of sharks in my time, from little white tip reef sharks in Thailand to schools of over 50 hammerheads in the South China seas. There is nothing like jumping in the water with a top level predator to get the heart racing.
However my first ever experience of a shark underwater was dead, laying on the bottom of the ocean with it's fin cut off. Shark meat isn't worth much, so it's quite common to slice the fins off a living shark and then throw it back in the water to slowly drown. As such, I chose to do my talk on the terrible shark finning trade around the world.