How about adding an option to filter featured questions by the value of their bounty? I.e. I want to challenge questions with bounty above +250 and would like to find them easily.
I agree this would be a nice feature:
But realistically it is quite a big task.
In the mean time, I whipped up this query that will list questions with bounties from the start of the month: (direct link)
SELECT P.id As [Post Link], V.BountyAmount, V.CreationDate As [Bounty Start], P.Score, P.ViewCount, P.Title, P.Tags, P.Body, P.AnswerCount FROM Posts P INNER JOIN Votes V ON P.Id = V.PostId WHERE DATEPART(m, V.CreationDate) = DATEPART(m, getdate()) AND DATEPART(yyyy, V.CreationDate) = DATEPART(yyyy, getdate()) AND V.BountyAmount > 0 AND P.ParentId IS NULL ORDER BY V.BountyAmount DESC, V.CreationDate DESC