TexasMike once bubbled...
I agree that you can pull out all the trash you desire out of many lakes.
And Travis always amazes me. I can usually find plenty of bottles and cans just outside of the booms that protect the diving area. And one time, I did a deep swing dive (tie off reel on rock, play it out, and do a big arc until you hit the wall 180-degrees from start) at the bottom of the wall at the dam site and found a bicylcle and 2 propane bottles (1 still had it's regulator). Wasn't carrying lift bags with me then so they are still out there, I guess.
Here's an interesting idea for a thread... name the most unusual thing you've recovered on a dive.