a teacher's research and experiments with the 'cloud'

Sorry, not the wine, but the ed tech resource called MERLOT (Multimedia Educational Resource for Learning and Online Teaching). I just joined, and it seems to have an almost overwhelming amount of information.
I watched five short videos on shifting powerpoint presentations (I’m a Mac/Keynote man myself) into active learning. According to the presentation by Paul Baepler, it has been established that most people watching a digital presentation switch off within 12 minutes, so it’s important to get students to do something within that interval. One example he give is “Think / Pair / Share,” in which you think of what you already know about the subject at hand, turn to a partner in the class, and discus your knowledge, and then consider what you and your partner might have to share with the class.
I’m fortunate to only have fourteen students in each of my classes, but if it was bigger class, I might encourage everyone to ‘tweet’ their responses. I’ve heard of very effective uses of Twitter in large lecture classes.