Oh thats just devious :)

[Hrusai]

reminds me of my "dodgier" days of buying certain pharmaceuticals, when arranging a dead drop we'd use those weird tombstone thingies on the side of the road near a drain (i think thats what your referring to aswell) that say something like seb 125 (i know it was seb something cause there was an "in joke" about a kid called seb lol), bloody handy they were

cheers for that NR, and you can extend it to any deliberate markings of letters or numbers!....what a superb system