Augmented Reality - or reality augmented ?

Augmented Reality has been around for a while, but the latest advances in technology are making it an 'actual' reality...

How could you do this in a non-digital way ?

John Davitt recently used clingfilm and felt tip pens as a lo-tech solution...

The Ordnance Survey demonstrated some ideas similar to this a long time ago. I remember being at an event at the Royal Geographical Society in 2005 ish when it was demonstrated.