Last November, MotherReader wrote: "I’d pledge my lifelong allegiance to the person who comes up with an ironic font--and no, the little winking emoticon isn’t enough." And that offers a fine topic to revisit as PUNCTUATION WEEK at Oz and End rolls on.
There are some other symbols beside ;-) to consider. According to Wikipedia, the Ethiopic languages already have a sarcasm mark. It looks like an upside-down exclamation point:¡ This mark is already programmed into many Western keyboards because it's used at the start of exclamatory sentences in Spanish. I rather like the idea of borrowing from Ethiopian culture, given its age.
The French poets Alcanter de Brahm and Hervé Basin proposed a punctuation mark for irony, as well as signals for doubt, certitude, indignation, and other emotional states. Most look like they'd belong in Dr. Seuss's On Beyond Zebra, but the irony sign is basically a backwards question mark. Alas, it was used in the Middle Ages for rhetorical questions, so in any exchange of letters with medieval monks it would simply cause confusion¡
Finally, as I wrote last fall, there’s the solution William Thornton proposed in 1793, of putting a plus sign on either side of an ironic statement or phrase. Supposedly, that's been adopted by Collegehumor.com since they're such big fans of eighteenth-century semiotics¡
But none of those symbols are fonts. By "font," I presume MotherReader meant a standardized variation within a typeface--a variation that can applied to any face. (As opposed to the recent use of "font" to mean a specific typeface with all its variations, such as Helvetica.)
Standard digital typography offers a plethora of ways to emphasize words.
We have italics, underlining left over from typewriters, boldface, ALL CAPITAL LETTERS, and even various colors.So theoretically we could take one of those styles and decree that henceforth it signals irony rather than emphasis. (I've already called for a halt to underlining for emphasis.) But using one of these formats would confuse some people. We need a style readers haven't seen before.
I propose that the best option would be backslant. Few typefaces have this style, but it would be relatively easy to create: it's basically the opposite of italics. And the fact that it makes letters lean in an unexpected way would help to convey a writer's ironic/sarcastic tone.
(Backslant examples use variations of the Roemisch Rueckwaerts Liegend typeface.)