When I read this question, my first impulse was to search for the countless other questions about sans-serif fonts. "sans-serif" yields 57 search results, yet there is no sans-serif tag. Would such a tag be useful (at least for potential questioners)?
Note that there's a texttt tag that features 6 questions at the moment. And no, I don't want to flood the starting page by retroactively mass-retagging old questions. But maybe sans-serif should be added to about a dozen questions with a high number of upvotes (or high-upvoted answers)?