CGI Programming on the World Wide Web
This is a free, online textook offered by O'Reilly. According to the author, "What will you encounter here? A variety of powerful applications that you can use and that will serve as models for your own CGI scripts. Among the complete applications in the book are an animated clock, a search tool, a survey, a quiz program, a game, a gateway to Usenet News, and an appointment calendar based on a clickable imagemap."