Currently we have a way of viewing the active questions, the newest questions & the most up-voted questions.
We also have a tab called 'Unanswered' where every question that has 0 answers (with a positive amount of votes) can be seen.
Most of the time these cover a broad enough spectrum to go about finding where to direct my attention.
However i would like to see a tab that shows all of the open questions with no accepted answers.
Having a tab like this would allow me to direct my attention to only those questions that are deemed acceptable but have no acceptable solution.
I feel this would be something used by more people than just me and i feel it could help improve the quality of this site as it helps direct peoples attention to those unsolved problems, and the more problems we have solved then the more useful this site becomes.
I realise this might be very similar to the existing unanswered tab, so i suggest doing what we do with the other tabs and give it sub-tabs.
for example clicking on Questions lets you choose between newest, votes, etc. But unanswered lets you choose my tags, newest, votes and no answers, i propose the no accepted answers tab be added to that bar along there