Seriously, Andy is the Chuck Yeager of XDI. He and his team at ooTao are pushing the XDI envelope as fast as it can expand. The OASIS XDI TC has taken the position from the start that it would like proposed XDI specifications proven out in implementations before anything is brought to a vote, and Andy is demonstrating this wisdom by starting to exercise the XDI universal schema and REST protocol model in very practical ways.
Use his i-name contact page to ask him about his XDI viewer that uses SVG to display XDI documents as visual XDI graphs, including showing how link contracts and rights paths automatically select the permissioned portion of an XDI document.
The Tao of XDI promises to be the focal point for many an XDI design discussion or revelation. Go Andy!