It stands for Do Not Feed The Trolls. And if you're a member of an online community, you're probably familiar with the term. Internet trolls post to online communities with inflammatory speech or speech designed primarily to get a rise out of people. The best way to keep them coming back is to feed them - that is, give them the indignation they want. The best way to get rid of them is to go all Freddy Krueger on their idiotic asses and totally ignore them. But trolls aren't necessarily confined to Internet communities. They're actually all over the media landscape. Wherever there's a channel of communication, there's usually some asshole trying to figure out a way to manipulate it to get people's goats.
A certain not-very-well-known agency announced that it was interested in hiring Neil French, the ex-WPP creative guy who made some very insulting remarks about women at a recent conference. It was so obviously a publicity stunt that I joined a chorus of industry folks in administering a most gratuitous verbal ass-beating unto the agency in question. What I should have done was simply ignore it.
Maybe I should get hats printed up with DNFTT on them.