You're probably familiar with the Keep Calm and Carry On posters by now. According to Wikipedia, the poster was "produced by the British government in 1939 during the beginning of the Second World War, intended to raise the morale of the British public in the event of invasion. Seeing only limited distribution, it was little known. The poster was rediscovered in 2000 and has been re-issued by a number of private sector companies, and used as the decorative theme for a range of other products."
Well, as this article by Maria Bustillos in The AWL discovered, the copyright war that resulted from the use and selling of products based on that posters has escalated to a competitive level of disturbing proportions.
Fast-forward to late March of this year, when unbelievable prat Mark Coop, an ex-TV producer whose credits include "Who Wants To Be A Millionaire?", succeeded in obtaining an EU trademark for the phrase "Keep Calm and Carry On." Coop had established a business selling Keep Calm products online in 2007 (and, as Megan Hustad noted here a couple years back, he was soon doing so well he brought in his mom to help fulfill orders). The Telegraph and others reported that Coop's UK trademark application was denied, but the EU one breezed right through. Soon after the EU trademark was granted, he started enjoining his competitors from selling Keep Calm merchandise on eBay, apparently by notifying eBay that he was the trademark owner and asking them to refuse access to certain vendors, as blocked competitor Kerry Cade explained to the BBC last week (starting at 1:00).
While you're here, check out also this mini documentary on the history of the poster and its rediscovery.