What's up with the @ symbol?

[David Presents]

Okay, so @ means "at" right? But are there really people so lazy they needed to invent a symbol for a two-letter word? Personally, I think it would make a lot more sense to use it to stand for a really long word, such as, well, antidisestablishmentarianism, for example. In fact, from now on, that's what I'm going to mean whenever I use @ on a post here on TMF. The only problem is, I can't say I really see myself using that particular word especially often....