The Laptop Expertise (CT) program has been developed to provide coaching in the ideas underlying the design of modern laptop systems. The TX-0 (Transistor eXperimental – zero”) is the first common-purpose programmable computer built with transistors. For straightforward substitute, designers positioned every transistor circuit inside a “bottle,” just like a vacuum tube. Constructed at MIT´s Lincoln Laboratory, the TX-0 moved to the MIT Research Laboratory of Electronics, where it hosted some early imaginative assessments of programming, including writing a Western movie shown on tv, 3-D tic-tac-toe, and a maze during which a mouse found martinis and have become more and more inebriated.