OK, I realize this is an embarrassingly simple use of the iPad in teaching, but it is one of the best I have experienced in this experiment. I am remaking parts of a course I am teaching this semester as I go, after becoming dissatisfied with how things were going earlier in the semester. That means that I am unusually dependent on notes I have written for class -- usually writing notes is enough to prepare me to navigate through a session without them -- but I also want to be able to highlight them for later revision in light of how the class conversation goes. The iPad, using GoodReader, has been a nice tool for that. A quick glance now and then keeps me oriented to the plan I set for myself and my students and a swipe here and there at the screen allows me to go back later and rework things.
Luddite that I am, this is as good as it gets!