Piss Off Door Mat - UrbanOutfitters.com
http://www.urbanoutfitters.com/shopping/product/detailmain.jsp?iMainCat=336&iProductID=8371&iSubCat=593&itemID=8371&itemType=PRODUCT
"Seriously sturdy, with a non-slip backing and subtle Anglophile-centric message for visitors. In the end, they can't say they weren't warned."