Thanks to this post from Dave Delaney, I was pointed to this article from Serious Eats about street vendors using Twitter to announce their locations, specials and other information important to their mobile customers. The South is not generally known for their proliferation of street vendors, so the only listing is for OnlyBurger in Durham, and it was added when suggested in the comments. They are a perfect example of the kind of mobile business that can thrive using Twitter. Their mobile kitchen tweets their location as they drive around Durham.
I have read many reviews of their burgers on various Durham food blogs, but haven’t sampled them yet. I will take this opportunity to seek them out over the next couple of weeks and try their burgers.