I had to read the lead in about Reader P. S. to realize that the hed was ambiguous. I will admit that you don't have to work as hard to misunderstand it as you do for some of the "arrested with gun" versions in that thread.
@Faldone: On the contrary, I read the hed before noticing P.S.'s remark, and I immediately latched onto the unintended reading. The correct reading didn't dawn on me until I had read the whole lede (although I wasn't really trying very hard to puzzle out what the hed was trying to convey).
@Brett: Well, until I read your comment, I was thinking that they missed the words "attackers from" to lead to this disaster. If not for your comment, I would never have gotten to the intended reading (Researchers find [25 countries (are) using surveillance software])
Oddly enough, I had to look to find the unintended meaning. I suppose it's because my default is that the PP attaches to the immediately preceding noun phrase rather than the more distant one, and there's nothing semantically unlikely about that reading.
Like Jeff Carney, I totally crashed, but the issue for me is not what the PP attaches to. After I read "find" + NP, I thought the NP was the direct object of "find". Here's an example of where a sentence is much clearer when a subsidiary clause is introduced by "that" than when it isn't.
Like Sarah I had to look at this several times and do some thinking to come up with the "wrong" meaning, but once I saw it it was very obvious. Something like looking at those curious perspective drawings that the brain can interpret in two differentways.
I got the intended meaning (only) at first. My initial response was 'why is this news?' because bluntly I'd be astonished if there were *ANY* country on earth not using surveillence software. It was not until a beat or two had gone by, and I thought, 'hey wait a minute, this is Language Log not EFF,' that I went back to look for (and immediately notice) the ambiguity.
In this case the unintended meaning is nearly nonsense, because there are very few classes of surveillence software that would have any utility for finding countries; furthermore, we live in a world where all the countries are known (I omit secret nations posited by conspiracy theorists — there is no credible evidence).
I agree with Ray Dillinger that the correct reading of the headline doesn't seem like news. Perhaps that's why, after getting the wrong reading first, I just could not figure out what the headline could mean (the wrong reading not making sense as a correct reading) until I actually read some of the article, where we get more details.
Like Ray Dillinger, I saw the intended meaning on first pass because I didn't think of "countries" as being what gets found with surveillance techniques. If the text had been "Researchers Find 25 Insurgent Cells Using Surveillance Software" then I would have been perplexed.
I just noticed that applying the correct reading of the hed to reader P.S.'s comment produces a reading as likely as the correct reading of the hed. I.e., by some undefined means it would be possible to find 206 countries that use Wikipedia.