What makes a question (and its answers) worth sharing?

Question

This is a spinoff from Brainstorming solutions to grow this site?.

From the Stack Overflow blog A Recipe to Promote Your Site:

Encourage your community to share links to outstanding questions and answers. And if you feel you're not producing outstanding questions and answers worthy of sharing with the world, endeavor to fix that first.

I participate in a weekly chat on Twitter that is designed for people to share and re-tweet links to their new blog posts and/or other news items worthy of promotion. Since I don't blog, I've been sharing links to Qs and As here. I started with my own Qs and As (since that's my writing just as much as if I had posted it on my own blog) and later extended it to other Qs and As.

My feeling is that we need to follow the advice I quoted above. Let's clean up our act and look at what we can do to make our Qs and As more worthy of sharing. Post your suggestions for ways we can improve below. If you're drawing a blank about what to do to improve, look over Meta and find older questions that can be linked in here.

What Q/A would you show off to a newcomer as an example of a really good question and answer -- which are your favorites, and why?

Links to related discussions:

• Style Sheet proposal: Consider sharing, previews when writing question titles
• Why put actual questions in question titles?
• Questions with the tag 'scope'

Answer 1

I'd like to offer for your consideration one of my recent favorites: What "hidden" clues are there in the GRO Indexes of births and deaths?

Online-only genealogists don't have the same insight about historical records and their indexes that old-school, boots-on-the-ground genealogists do. With this question, we can get back some of the insight that comes from handling the physical indexes.

The information is also useful to anyone who is doing research in England and Wales. It isn't limited to a small jurisdiction or a particular surname study.

Harry's brilliant Q/A gives us a fresh look at a common reference. This is the kind of thoughtful analysis I want to see on Genealogy.SE.

I've shown my appreciation by awarding a manual bounty.