Chuck Guzis wrote: To be certain, some errors/additions are deliberate; Rand McNally generally sprikles a few non-existent landmarks in their maps; Google satellite maps have "watermarks" that can be very confusing. I spied what looked to be clearing on some of my forested land and hiked to the very spot and found--trees, just like everywhere else. It took some conferring with a USGS employee to discover that what I thought was a clearing was a rather subtle watermark (viewed in just the right way, you can make out a "Go". Cheers, Chuck ------------------------------------- Billy wrote: It also happens closer to home in our mutual field. In the 1970's, CDC was working hard on Russian alliances. They had to prove that Russian technology was as advanced as the products CDC wanted to ship. (The old DoD guideline.) So they bought some Russian 8080's and tested them. Everything was going good until they decapped the chip. Inside, under a microscope, they found an image of Mickey Mouse's head in the metal layer. Of course, put there by Intel engineers to spot copy cat reverse engineering. The Russians hadn't caught up in technology; they had bought masks under the table and made complete ripoffs. I know other IC vendors use similiar tricks to identify their IP. One I have seen is an entire section of circuitry that has no outputs - like the old famous write only logic. And it has been faithfully copied by several Asian suppliers. Billy