I've been looking around for a way to do this and I can't find a solution. I want to have a search page where I can search for posts based on different criteria. You would have a search bar, but then you could select categories in a dropdown, author, custom fields, et cetera, and your results would reflect that criteria.
Furthermore, you could prioritize the results by sorting criteria. For instance, you could select an author, select a category (or a couple categories), and you could also drag those fields up or down, so if you dragged author to the top, the results would return all posts by that author in the specific category, then any author in that category.
I haven't seen anything like this, but maybe there's a way to use a couple plugins in tandem to get the effect. What do you think?