@Jason ~ no, but close. Actually its from Brad Dalton. I saw it here [ http://wpsites.net/web-design/how-to-make-your-nav-menu-sticky/ ] and thought it looked like a really simple solution. Which it was, since he left out the whole media queries bit, which is unusual for Brad as his stuff is usually pretty spot-on.
Fortunately, he’s take pity on me and he’s taking a look, so I should have an answer pretty soon now.