As already mentioned, this can be done using SEDE.
The posts with highest $\min$(upvotes,downvotes): main, meta
You can also modify the query to include some additional information about the post (e.g., the post owner): main, meta
IIRC the Votes table includes the votes on the posts that already have been deleted - so it is possible to get some stats also about deleted posts: main, meta
Since the syntax is the same - it suffices to replace the table Votes by the table PostFeedback, here is the same query for votes coming from the anonymous feedback: main, meta. For more info on the anonymous feedback, see the links in the tag-info. (The anonymous feedback was mentioned in a discussion on this meta about downvoting: How to deal with "discomforting" downvotes?)