It might be interesting to know what the tour guides plan to do on their trolleys. I was once on a trolley where the tour guide led the passengers in singing Christmas carols. I've been on other trolleys where the tour guides cracked jokes or asked Somerville trivia questions. I was even on a tour once where the mayor was the tour guide, and he asked Somerville trivia questions and gave out Somerville Rocks T-shirts to people who answered correctly.