I love the art work.  Does anyone know how the keys are able to be changed?  Another question about these beautiful paper wallets suitable for framing is:  How can we know that only the specified number of prints are actually all that were produced.  In the 8.5x11 format only 200 of each print were run.  Seems like a crypto method could be applied to validate the legitimacy of the actual art piece, while allowing me to stash BTC in the keys.  I am eager to play with this, and just like the art so wont lose too much sleep over the investment.  I love Alexander Federov's work.