This was one I was looking forward to: I planned to join in on a drum circle advertised in the local paper. It was supposed to be at the pier at 9 AM, and open to anyone. A drum circle - a bunch of people sitting around banging wildly and freely on drums - is the sort of thing I'd HATE, which is exactly why I was dying to try it.
Alas, I got there and there were no drummers to be found.
I waited and looked for a half-hour and - when I finally accepted that it wasn't going to happen - I took a seat on the pier & just watched the world go by for a while...not what I wanted to do, but an OK moment for my life list anyway. Sometimes things don't go the way you planned and you have to march to the beat of a different drummer.