For all the millions and billions that are being burnt up by the governments of the world, it seems that a little human ingenuity can still go a long way in fooling the best and most expensive security systems that we can install. Take the Japanese airport at Tokyo. Japanese authorities spent almost 40 million USD to install a sophisticated fingerprint reader which makes everyone that passes through the airport security instantly compared across a Japanese database.
A South Korean woman who had been departed from Japan previously managed to beat the systems and get in again by simply using tape on her fingers to fool the machine. Officials now believe that many others may have entered Japan using the same technique.
Lets just hope Homeland Security is doing a better job - I do have my doubts on it though.