Unsuccessful in finding the bit for my tripod. It's apparently very old. I have a list of stores to try.
I dropped off and picked up a roll of pictures from South End Photo. Interesting results. Must experiment more.
I started taking the match.com attraction test, but I got interrupted with a phone call at the point where you have to pick faces that are attractive to you while they are rapidly shuffling in new faces. No pause button, so the test was pretty much blown. Not enough interest right now to re-take the test.