I sometimes whish to use advanced searches to filter specific time windows. One could filter based on when a question was asked, or when it was last active. You might want to suppress brand new questions, or even go hunting for questions old enough to not show up in the homepage at all, but still fresh enough that the OP still is interested in an answer.
As far as I read the current documentation, there is no way to achieve this. But I guess it shouldn't be too hard to get something like this implemented. The most difficult part might be deciding on a suitable syntax, so I'll hope that answers to this question here might propose posibilities which can be voted upon.
As filtering by time makes sense in both directions (older or newer than a given date), most solutions will probably include some form of inequality specification. That in turn might be applied to other quantities, like votes, answers, upvoted answers, and so on, to further extend the power of advanced search.