By the rule of Muphry's Law, this Daily Mail article ought to be chock-full of errors, as should the comments. It's about 'Grammar Man', who has been taking a white marker to the graffiti in Kent, correcting the punctuation and grammar. Here's the example all the papers have been using:
The article notes that Grammar Man is himself committing an error by using a capital L in the phrase 'English Language', and unnecessary capitals throughout his corrections.
Muphry's Law states that if you write anything criticising editing, proof-reading, and general lapses in writing skill, there will be an embarrassing error in what you've written. Grammar Man has indeed fallen prey to it, but it's somewhat astonishing that not only is the article itself clean, as far as I can see, but so are the comments (apart from deliberate errors for 'comedy' effect). One commenter does think that 'misspelled' in the headline ought to be 'misspelt', but I think that's allowed variation.
We must conclude that Muphry's Law is not universally true. More on the news story here.