Here’s the original question and answer:
“I’m writing to enquire about your use of the first hyphen in the phrase ‘clearly-labeled stand-alone tutorial’ (in your recent article titled ‘Are chapter numbers necessary?’). The references that I use at work (Chicago and Gregg’s) recommend against such a hyphen. Do you use a different reference that mandates this hyphen?”

I answered,
“No, in that case I used it because there were four words in a row modifying ‘tutorial’ and it seemed more clear (and more balanced) to hyphenate each set of two. That first hyphen isn’t necessary, and as you say, standard references these days recommend against it. Actually, I think I use it mostly because back in the dark ages when I studied grammar (which was taught in schools in those days) then that hyphen was more commonly used. But I could be misremembering.”

Until its OED entry is solemnized, we’ll have to settle for this definition on Wiktionary: “grawlix, n. A string of typographical symbols used (especially in comic strips) to represent an obscenity or swear word.” I don’t think I’ll ever look at a character set quite the same way again.

The sneakiest way to use a hashtag is to set apart a word or phrase or name in your tweet and make it look like you very accidentally blurted it out, which is an extension of the muttered-into-a-handkerchief usage, but with a slight Freudian twist. Here, the hashtag is like a bit of chicken wire between what you are consciously and deliberately saying, and what just happened to slip out, especially useful when you are making a comment and pretending that you absolutely, positively will not name names, and then, whoops, it just came tumbling out. A hashtag is not a secure perimeter, after all! Just look at how holey a hashtag is—it’s only chicken wire, and sometimes things—bad things, names and particulars, details, information, those sorts of things—do manage to make it through. To wit:

“I just made out with your husband! #kidding #hewishes #likeIwouldadmititanyway #ToddPalin”

Amazing how rich and complex 140 characters with a few symbols thrown in can be.

If the multiplicity of irony marks created over the centuries suggests anything, it is that irony must be peculiarly tricky to communicate in writing. And if the subsequent failure of each and every one of those marks to gain anything approaching mainstream acceptance is anything to go by, it is unlikely to get any easier.

How to type symbols, accents, special characters, and weird punctuation

An understanding of typographic etiquette separates the master designers from the novices. A well-trained designer can tell within moments of viewing a design whether its creator knows how to work with typography. Typographic details aren’t just inside jokes among designers. They have been built up from thousands of years of written language, and applying them holds in place long-established principles that enable typography to communicate with efficiency and beauty.

Handling these typographic details on the Web brings new challenges and restrictions that need to be considered. Below are a few rules of thumb that will have you using typography more lucidly than ever before.

Like the ampersand, the ‘@’ symbol is not strictly a mark of punctuation; rather, it is a logogram or grammalogue, a shorthand for the word ‘at’. Even so, it is as much a staple of modern communication as the semicolon or exclamation mark, punctuating email addresses and announcing Twitter usernames. Unlike the ampersand, though, whose journey to the top took two millennia of steady perseverance, the at symbol’s current fame is quite accidental. It can, in fact, be traced to the single stroke of a key made almost exactly four decades ago.

Both sides are understandably protective of their version of the language, so it was a pleasant surprise to find Ben Yagoda of Slate praising the "logical punctuation" that we are said to use in the UK. Specifically, he notes a "punctuation paradigm shift" away from the traditional US practice of placing commas and full points (periods) inside quotation marks.

The dawn of the web has frequently been compared to the invention of the printing press. But the web has also destroyed one of the greatest features of nearly every press since Gutenberg: the ability to publish pleasing type.

The printing press gave us type that was clearer and easier to read than that produced from a typewriter, because the typesetter had additional tools at his disposal—and knew how to use them. The web has cost us some of those tools.

A punctuation purist would claim that emoticons are debased ways to signal tone and voice, something a good writer should be able to indicate with words. But the contrary is true: The history of punctuation is precisely the history of using symbols to denote tone and voice. Seen in this way, emoticons are simply the latest comma or quotation mark. And despite the oft-repeated story that Carnegie Mellon professor Scott Fahlman invented the smiley and the frown face all the way back in 1982, the history of emoticons goes back much further.

"Colons, once on life support, are proliferating.

Why?

Because these aren’t Ms. Truss’s colons. The colons of Eats, Shoots and Leaves, are brittle, dusty, soporific. “Prepare yourself,” they yawn, “that I may shortly provide you a list.” To actually call these colons by name (syntactical-deductive, appositive, etc.) is to virtually lose consciousness. So bear with me for a moment as we first rechristen our colons."