This sounds very similar to Microsoft Research's concept 'Penny Black' - which, worth noting, was itself inspired by real postage history. http://research.micr

This sounds very similar to Microsoft Research's concept 'Penny Black' - which, worth noting, was itself inspired by real postage history. http://research.microsoft.com/en-us/projects/pennyblack/ http://research.microsoft.com/en-us/projects/pennyblack/