Dutch 10 guilder note. Holland and Lebanon are the only countries to have issued banknotes with bar codes. One of the interesting things that we've all learnt about Bitcoin is that it isn't actually anonymous, it's pseudo-anonymous . While anyone can deal in bitcoins without providing personal information like a phone number or photo ID, all bitcoin transactions are broadcast to the public. By analyzing these transaction patterns, it may be possible to flush a user's true identity out into the open. Bitcoin is an attempt to digitally replicate many of the features of the old fashioned banknote, but even banknotes are to some degree pseudo-anonymous. Each banknote has a unique serial number on it. By tracking serial numbers, it may be possible to connect a note to a noteholder and thereby destroy their anonymity. The process of unveiling note users occurs most often in kidnapping cases. When their young son was kidnapped in 1932, the Lindbergh family paid a $50,000 rans...