Just heard about Liquid Threads . . . .
Speaking of sort features using drop down menus, and viewing options here is an idea for a wishlist:
What about the ability just to show a collapsed version of just the headers without the corresponding message text?
You could use the "Permalink" to expand the thread or reply to view the text. This way an active discussion with many posts doesn't get too long (thus avoiding unnecessary scrolling).
Perhaps this is in the too hard box for now and not a major priority at this time.
Well, our secure funding runs out in two weeks, so I'm a bit careful to add to the wishlist (though being open source, of course anyone can add to the feature set). I have suggested to David a table of contents for longer talk pages as a navigation tool, which I'd prefer to collapsing the actual threads, at least in the default view.