I love retro/old-technology computers, like the Apple II and C-64. One of the cool parts of Discovering Computers 2008 is a small section called Technology Trailblazers which brings to mention the early days of computing. In chapter 3 it mentions Dan Bricklin and his program, VisiCalc, which was one of the earliest spreadsheet programs. VisiCalc was originally written for the Apple II platform and as a result these computers were found in businesses all over the world in the late 1970s and early 1980s. Possibly, without VisiCalc, there would not be the Apple computers of today.
Dan's Webpage is a great resource. It shows old screenshots of VisiCalc in action. You will notice that Excel was developed with VisiCalc as its guiding light. Dan was not able to copyright his program, but you'll have to visit his page to find out why. It is also full of podcasts, feeds, and other little goodies, but its not technology heavy making it very easy to navigate.
Today, Dan runs a software company called Software Garden and he has just released an open source version of a new spreadsheet program, called wikiCalc. I know very little about programming, but my interest has been piqued as a result of LIS 2600. I hope to explore it a lot further and may use wikiCalc as a vital part of that learning process.