Transistor
The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. Julius Edgar Lilienfeld patented a field-effect transistor in 1926 but it was not possible to actually construct a working device at that time. The first practically implemented device was a point-contact transistor invented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley. The transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement.
Norman Krim
According to Jack Ward's "Semiconductor Museum", Norman Krim is credited to inspire the transistor hobbyist and experimenter market with the creation of the CK721 and CK722. As Jack Ward, curator of the Semiconductor Museum website states, ""Many of the talented and dedicated professionals and amateurs who have been responsible for the tremendous rise of the electronics industry over the past four decades can still remember the time when, as a young hobbyist, they were able to scrape together enough money (maybe through saving allowance or cutting the neighbor’s grass) to buy that first CK722..."" From the CK722, came articles in electronic magazines, books and pamphlets on do it yourself building projects and competition from Raytheon's competitors notably General Electric who following Krim's lead of recycling out of specification transistors came up with the 2N107 transistor.