All I can say is I want one. Heck, two. While wandering the aisles of DEMA, I stopped and spoke with Lawrence Groth of Shark Diving International, who had my favorite piece of equipment at the show a motorized shark cage. It can operate for up to five hours, and the possibilities are unprecedented for shooting both still and video images of great white sharks pursuing their normal daily routine of hunting and mayhem to mating. Strap on the rebreather of your choice and a warm drysuit, and the motorized cage can patrol the waters of such sharky places as Guadalupe at depths of up to 100 feet and speeds of up to 5 knots. At those speeds, a full-face Aga-type mask works best and won't get separated from your face.
Check out the cage at www.greatwhiteadventures.com.