TED.com is one of my absolute favorite Web sites. You can watch fascinating speeches about science, entertainment, business, culture, arts, and anything else under the sun. The speeches are often funny or touching, and they are always informative and thought-provoking. Many of the speeches I’ve watched have been between 15 and 20 minutes.
Advanced listening or speaking classes first come to mind when I think of TED, but really an activity for any class could be designed around a speech from this site. If nothing else, you should tell your students about it. They’ll be able to find topics that interest them and watch the videos at their own pace, rewinding as necessary.