I like to consider myself a knowledgeable user of Windows - there's aren't too many nooks and crannies that I haven't explored and/or tried.  Today, however, I was introduced to a feature that I can't believe I didn't know before.

When presented with a Message Box dialog, simply press CTRL+C to copy it's contents to the clipboard.  So easy...so elegant...so brainless...so non-intuitive.