I have never taught a fully online course before, but I have integrated several Web 2.0 tools into my face-to-face classes. I have used Blackboard's discussion boards, wikis, journals, and anonymous grading tools in my classes.
As a graduate student at UC Davis, I took a semester long seminar on creating a hybrid class through the Department of Education. They encouraged us to utilize a state of the art studio they had built for creating teaching videos. I took them up on the offer and made a short series of videos that covers the same lectures I give about the nature and value of philosophy to every introductory class I teach. I use a 'Mystery Box' to teach my students the difference between metaphysical and epistemological questions, and to show that that even if we cannot ever know that we have the right answers, there are, nonetheless correct answers in philosophy, and we can provide reasons for thinking some answers are more likely to be right than others. The videos are on my YouTube channel here.
More recently, I took a graduate level course on designing and implementing a fully online course. As a final project, I experimented with Moodle, and created a fully online teaching module around the videos described in the last paragraph. The module involves quizzes, and other tasks for the user to complete to both reemphasize the points I want them to remember, and to assess their understanding. Answering a quiz question incorrectly automatically results in corrective feedback and an opportunity to try again. The modules can be viewed here. *Note, you do not need a username or password to view the modules. Simply click the 'Log in as a guest' button.