Eben Upton is best known as the man behind the Raspberry Pi, a tiny, $25 computer designed to help turn kids into programmers. Upton priced it at $25 because he thought that's around what an average textbook cost: "I now understand that's an incorrect estimate. If we had a better idea of what school textbooks cost we would have had an easier job with the engineering over the years," he joked to Wired years later. It's a funny story but also a sad story. Textbooks are expensive. More expensive than most non-students even realize.
