I was wondering outside the dealer's room at a local gaming convention about 2 years ago when I came across a side room that had several long time gamers sitting around in a circle. They were shouting numbers at each other, things like "63!" and "127!" Everyone laughed when a number was shouted.
I watched for a few minutes, trying to figure out what was going on, but I couldn't. So, I decided to be nosy and ask someone near the door I was standing at.
"Excuse me sir." I said to some one who looked like Elminster incarnate. "But could you tell me what's going on?"
"Sure," he said. "We're old friends who've been coming to this gaming convention for 15 years. Well, we know all each other's old stories, so one year we numbered them and now we just shout them out."
The very concept struck me as odd, so I thanked him and continued to watch a little bit longer. After a minute or two, someone shouted "163!" and everyone fell off their chairs laughing. The guy I talked to was laughing so hard that tears were streaming down his cheeks. I couldn't hold in my curiosity, I had to know. "What? What was so funny?" I asked Elminster. He gasped for breath and said, "Oh! That was one we hadn't heard yet!"