From Tom Scott's 'Making Stuff Happen' blog:
It seems a bit strange to me that the media carefully warn about and label any content that involves sex, violence or strong language — but there's no similar labelling system for, say, sloppy journalism and other questionable content.
I figured it was time to fix that, so I made some stickers. I've been putting them on copies of the free papers that I find on the London Underground. You might want to as well.
Go to his website and print some for yourself.
We bought a box of 6,500 labels for $25 from Officeworks.