the generalized form of this technique (which you can also use to see if somebody has a font installed locally) is to basically create two rules:

    .load-base { font-family: comicsans-ms, verdana; }
    .load-test { font-family: fancyfont, comicsans-ms, verdana; }

and periodically check that the width of a line of nonsense text for both classes is not the same. Blank has the obvious benefit that it will be obvious when 0 != something else, but you can do it if you have some reasonable expectation that some other common font will exist with different metrics than your fancy font.

interesting to see the process behind the font, though.