We are lucky to have great videoconferencing facilities at NU. Even if your classroom is not equipped as a videoconferencing studio, simple webcam will do the trick! So, how can you use videoconferencing for instructional purposes? Possibilities are endless: connect with the experts in the field, have a virtual field trip, provide opportunities for your students to work on collaborative projects with students in other universities and in other countries, conduct a class while you are travelling, etc., etc., etc.  And you can check my diigo collection for more ideas and tips.