<p>Perhaps some stupid answers, but ones that come to the top of my head:</p>
<ul>
<li>I don't know how this generally works across the Stack Exchange, but I'm wondering if there can simply be an &quot;old questions&quot; review which automatically pulls old and unanswered questions and allows people to vote on whether they should remain or be deleted. Something that would be particularly useful is a feature that you can vote on questions that the user clearly won't accept answers on anymore (e.g. user posts question in 2012, gets answer in comments, says thanks, and never sees the site again).</li>
<li>Perhaps some kind of bounty-based system where a user is rewarded for doing similar actions. E.g. a mod puts up some bounty for clearing 100 or so reviews of old questions to clear the bin. To perhaps minimize <em>how much</em> of a bounty, it could also be in a contest format where the person with the most reviews gets a set amount, with a 1st Place, 2nd Place, and 3rd Place award given.</li>
<li>Some kind of badge to the same effect (perhaps in relation to the first point).</li>
</ul>
<p>I feel there would probably have to be <em>some</em> kind of incentives to really get that ball rolling, hence the suggestions.</p>
