In chapter eight of his book, Will Richardson explains in detail the benefits of the various kinds of "casting" a teacher can do- podcasting, videocasting, screencasts, and the like. Having encountered these media in my daily life, as well as creating them in other classes, I can definitely speak to the benefits they can have in the classroom. As a teacher that implements Edmodo in the classroom, I had often found myself inundated with questions about how to perform some of the more basic tasks on the site- opening an attachment, completing an assignment, or attaching work to a post. To address this issue, I created screencasts that guided students through some of the more common functions- this allowed me to spend less time addressing procedural issues in class, and more time addressing content and knowledge gaps.
Of course, I can see applications of this for content as well- it makes a lot more sense to record the in-class goings on than to try and catch absent students up during the few moments you can spare with them. I have also used such videos as an aid to my direct instruction as well. On the whole, these technologies can do much to address some of the stress that teachers face.
References: Richardson, W. (2010) Blogs, wikis, podcasts, and other powerful web tools for classrooms. Thousand Oaks, California: Corwin