Roo Reynolds’s Inky-Linky is a bookmarklet that makes printed-out webpages much more useful by adding QR codes to the margins, corresponding to the links in the document. That way, you can follow the links in your hardcopy by scanning the codes. It’s available as a tarball on GitHub, and will probably not be usable to you if you don’t run a local web-server, but it points in a very interesting direction!
