Those heading to the video store or movie theater this weekend who are unsure about what movie to see may want to consult MovieLens. MovieLens, from the Department of Computer Science and Engineering at the University of Minnesota, is "a free personalized movie recommendation service" that uses technology called Collaborative Filtering. The service works by querying you about movies you have seen and what you thought of them. This information is then compared to other MovieLens users' answers and ranked to arrive at a list of personalized recommendations for you. Your personal selections may then be limited by genre, film or video format, and currency. Many recommended titles also provide links to promotion pages for the movies or the Internet Movie Database, which provide additional information about the movies that can help the undecided in their selection.