Careful driving isn't the law in England--just a veiled suggestion--eh, Graham? *G*Re the "crossing" signs, I knew of a guy who had one made up that said "SLUG CROSSING." The he collected a bunch of the little critters from his garden, placed them single-file across his sidewalk, and snapped a photo of them crossing in front of his sign.
BTW, I think we have BEAVER CROSSING signs in appropriate places in Oregon. Do they have ARMADILLO CROSSINGsigns in Texas?