Lenticular printing results in two sets of images being visible, according to which way the surface is viewed. This is the same principle that is used to create the Lickticular Choc Ice.

Lick it from the bottom up, and you get one flavour as your tongue slides across the downwardly angled frozen surfaces. Lick in the opposite direction, and you get a different complimentary flavour.

Of course the full effect doesn't last that long, as the angles soften and melt level, and the tongue then simply crosses the alternately flavoured stripes, but it's fun while it lasts and promotes great antics to control the tongue movements needed to achieve the desired result.
-- xenzag, Jan 21 2014

lenticular printing http://en.wikipedia...Lenticular_printing
licktickular effect is acheived using a magnified version of this principle, only frozen in ice [xenzag, Jan 21 2014]

This is just two good.
-- 2 fries shy of a happy meal, Jan 21 2014



random, halfbakery