It's amazingly effective - provided you get the phrase right. It's quite easy to mis-recall, but for articles that strike me, there'll often be an arbitrary fragment that stays with me. It's even better if you happen to recall the end of one sentence and the start of the next - then, even two words can be enough.
BTW: I found this (but it hasn't been submitted here): http://www.librarything.com/topic/98543 It's an example of someone actually doing this. Here's another http://glovepie.org/forum/viewtopic.php?f=2&t=185&st...
Or this? http://news.ycombinator.com/item?id=1532251
If not, can you remember any specific words that were definitely in the post?
What do you really remember?
How recently? Can you remember what else you did that day? Can you remember what time of day you saw it? All these things can be used to find a short list of titles for you to skim read to see if you recognise it.
But I'm going to bed, so it won't be me. Good luck.