"The national ID program hopes to clear up current bureaucratic tangles common in India, where citizens might be issued almost 20 different forms of identification. Adding to the confusion, many of those IDs don't work in different parts of the country." (2009, popsci.com)

The article also mentioned that if you stacked up the cards on top of each other, the resulting pile would be 150 times taller than Mount Everest. That's a lot of cards.