Bank notes

[Douglas Sinclair <dsinclai@acs.ucalgary.ca>]

Canada now uses holograms on its $20, $50, $100 and $1000 bills.
They're a small patch on the top right hand corner that looks like gold foil.
Written on this foil is the denomination of the bill (20, 50, &c).  As the
viewing angle is changed, the color of this writing shifts.

Obviously, this will blow a photocopier out of the water.  I have minimal
experience in holography, but it would also seem to be difficult to print
one on a metal foil.
-- 
PGP 2.3 Key by finger