Inspired by a similar question on meta.stackoverflow, I just did this database query on serverfault, and found 262 pairs of questions with totally identical title, excluding those where one of them is already closed. (There are some merged questions in the list, if those were not closed before merging.)
In some cases these might be simple duplicates, then vote to close. (If you think the to-be-closed one has valuable answers, you might flag it for moderator attention, so it can be merged.)
In other cases one or both questions might have a bad title, then edit the title (and maybe the text and tags, if you are on it) to make them better (and distinct).