Actually, given they have just covered the damn Digital Economy Bill (now Act) it might be that as a campaigning organisation with no political links, 38degrees.org.uk might be a place to start.
I had been thinking that I could consider some wbesite called "www.shelves-of-shame.info" but I was (on a different project) hoping to get newsagents to assist me, so I'd be shooting myself in both feet if it ended up listing practically every newsagent in the country!
38Degrees accepts ideas for campaigns. They had 20,000 individuals support them on the run up to the Digital Economy Bill and quite a number donated so they could put some adverts in the newspapers about the bill being rushed through. (Not getting any daily papers, I don't know what was actually in the copy, sorry).
It strikes me that if a number of the big chains were bombarded by a few thousand e-mails in a few weeks time (enough time for people to widen knowledge via FaceBook, Twitter, on blogs, and so on) then if it was co-ordinated by 38degrees, it would allow for people here on MN to spread the word, and those on NM too, to mention it, without it being a campaign by "competing" websites.
Of course it might get wider support (on MN) if MNHQ made an issue of it, but 38degrees could probably do the technical stuff about gathering suitable e-mail addresses amd knowing which methods would (a) get the information spread to most sites, and (b) get the maximum embarrassment for the big names like the Co-Op, Tesco, Asda, Morrisons (?) Waitrose (?) and M+S plus the petrol station owners like BP etc (sorry, don't drive, don't even know all the big names... does Q8 still operate?)
It would be something if the multitude of stores all stopped selling the likes of Nuts because they had several hundred thousand e-mails complaining about their policy of carrying unsuitable magazines and trashy newspaper.
If they knew that they would lose even 10% of their food and electrical sales as a result of some junk magazines, I suspect they'd be shouting from the rooftops that they "no longer stock the following magazines: ....."
It might shock the MPs, too, that "people power" (co-ordinated via the internet) means they should look out if they come up with something that gets the public angry...
It's clearly short of civil disobedience, there'd be no arrests or demos needed, but it would need a bit of work on wording which chains are the target, what magazines and "news"papers they stock, and how their action is considered offensive/wrong.
Any volunteers?