Exbiblio was a company I started with Martin King, with the aim of bringing some of the power of digital media to paper documents.   I gave several talks about the ideas behind it; this one is from the GOVIS 2007 conference in New Zealand:

Exbiblio developed some early-stage prototype products, some interesting underlying technology, and a very substantial patent portfolio.  But, sadly, when Martin died in 2010, the company died with him.  The patent portfolio was acquired by Google.