Nerds of the world jump of happiness, for HP has brought the legendary HP 15C Scientific Calculator and the HP 12C Financial Calculator for the iPhone and iPod touch, complete with custom skins and programming. What are these “calculators” I am talking about, you ask? Please, allow me to pull a Chris Anderson here: The HP-15C was a high end scientific programmable. To the HP-34C’s numerical integration and root solver the HP-15C added complex numbers and matrix calculations. The HP-12C is HP’s longest and best selling calculator. Though it has been followed by many newer models, with both more and less features this model continues to sell well

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HP Invents Time Machine, Converts iPhone into Classic Calculator [IPhone]