I found a really neat one yesterday at the site of the "re-located" Cape Hatteras Lighthouse. I'll post a pic of it as soon as I get the film developed. The only drawback: It was placed by the North Carolina Geodetic Survey so it's not on any lists. Neat disc, though.
Coords: Zone 18S, 0451886 Easting by 3900989 Northing at >1m ASL.
Sorry for the UTM, but I'm just too tired to translate them now, besides, it's more accurate.