The awesomely named Rocket Sasaki challenged his engineers at Sharp to make the first solar-powered one.  
An early one of these devices from Sony known as the SOBAX was killed because Ibuka Masaru thought there was only a market for them amongst businessmen.  Nihon Keisanki, one of the sixty Japanese companies that made these things during their so-called "wars" in the 1970s, developed the world's first microprocessor.  Patrick Haggerty dreamed up a (*) palm-sized device of this type to sell the integrated circuits of his Dallas-based company.  The awesomely named Rocket Sasaki challenged his engineers at Sharp to make the first solar-powered one.  A man playing with one of these devices on a train inspired Gunpei Yokoi to develop the Game &amp; Watch.  Canon was the first to add a phone-style 10-digit pad to them.  For 10 points, the TI-83 is what type of device for making math easy?
An early one of these devices from Sony known as the SOBAX was killed because Ibuka Masaru thought there was only a market for them amongst businessmen.  
calculator [or graphing calculator