I think it would be helpful if there was an advanced search page. This could do the following:
- Allow user to select AND instead of OR
- Allow easy filtering by tags
- Allow easy filtering by user
- Allow searching of only questions with no accepted answers
- Allow searching of only questions with no answers
- Include an actual search button, allowing search via handheld devices
There would be a link to this search page on the footer of every page (no need to clutter the header).
A lot of this is already available, but requires the user to know all the "tricks" for searching on SOFU. This page would make advanced searches more accessible in general, as well as supporting some new functionality.
What else would you want to see on an advanced search page?