Internet-accessible information retrieval tools for advanced DB/IR courses

A number of information retrieval tools are now freely available over the Internet, either as full production programs or demos. These programs illustrate a wide variety of IR techniques, and can allow students to gain realistic, hands-on experience with a variety of algorithms that were previously difficult to discuss other than in theory. In addition, many of these programs are associated with computing-related document collections that in and of themselves are useful for computer science students.