Love the choices that people have found so far on You Tube.  I think You Tube and Teacher Tube have good possibilities for the teacher who takes the time to find something that compliments a theme, emphasizes a teaching point, stimulates discussion or serves an example of good technology technique. " Situations" happen most of the time with students and teachers when there has been lack of planning, previewing etc. on the part of the teacher. I see using You Tube as really no different in terms of being prepared and being clear about the purpose. We would expect the same with using DVD's etc. I enjoyed watching the following You Tube offering. Food for thought!  Enjoy!