<p>The <a href="https://stats.stackexchange.com/questions/13690/how-to-compute-the-probability-associated-with-absurdly-large-z-scores/13809#13809">network of cross-referenced posts</a> by @Cardinal on <strong>estimating tail probabilities of the Normal distribution</strong> is worth highlighting and memorializing: it's a clearly described, useful body of work.  To help us appreciate this better, a blog post could provide some background: why do we care about such tail probabilities, what are the applications, and what are the basic problems with computing them.</p>
