At IIT Training we strive for an inclusive pedagogy. So, we are always looking at new and innovative ways to engage adult learners with complex technical matters in a fun way. One of our senior technical trainers, Geoff, has asked for buckets of lego for a new hands-on session for our IPv4 and IPv6 courses. We thought it was for Open Systems Interconnection (OSI) model layering, but we were wrong, it was a whole lot better than that!....it was for the packet headers themselves, have a look what he'd come across: http://righteousit.wordpress.com/2010/06/27/practical-visual-three-dimensional-pedagogy-for-internet-protocol-packet-header-control-fields/