We reported a while back that the Royal Institute for Cultural Heritage (KIK/IRPA), Lukasweb, and the Vrije Universiteit Brussel, in collaboration with the Getty Foundation, was digitizing the Ghent Altarpiece in extremely high definition. In addition to making the digital images of the finished panels available, the project has used Infrared Reflectography (IRR) and x-radiography to look at the work in levels of detail that were previously unimaginable.
Visit the updated project site here, and prepare to be dazzled!