Working on a boat at Australias Great Barrier Reef, my favourite site was 'The Fish Bowl' I would take the guests past the clam gardens, show them where the anemones were, swin into the fish bowl and point out the larger pelagics, and the resident reef shark. Somewhere I would try to find a sea cucumber to carry, and I would end the dive on the far side of a cabbage coral by placing the sea cucumber in an TOILET! I would let them know that we were at the 'complaints department.' If anyone had any issues they wished to bring up, they could write them down and file them down there where they would be dealt with accordingly.
Other than that, I have found a bright pink towel zipping past on a drift dive. Sea grass and kelp were beginning to develop this towel an afro. I collected it and still take it with me on dive trips. It's a good towel!