This is not an Ovaltine commercial

Xerox Parc's site is one of many sites I check on from time to time. A long time ago I stumbled onto their page devoted to DataGlyphs, but I haven't mentioned the subject here.

They're next generation bar codes: "a robust and unobtrusive method of embedding computer-readable data on surfaces such as paper, labels, plastic, glass, or metal...flexible in shape and size. Their structure and robust error correction also make them suitable for curved surfaces and other situations where barcodes fail."

You can even create your own DataGlyphs with their GlyphServer Demo.