Inspired by some comments in Private Eye, today's question is should Letters Page be Letters' Page. On first glance, the apostrophe looks okay - the page belongs to the letters. But no, the page is just where the letters are, there's no ownership involved.
Let's take a more obvious example. I propose a Trousers Convention. With an apostrophe, Trousers' Convention would imply a gathering of trousers to talk about some other, unidentified topic. Without the apostrophe, we infer it to be a gathering of people to talk about trousers. There, easily done.