I've found that developing quick quizzes in Xerte, Moodle and Blackboard have been really useful tools to engage students with a concept early on in an online setting. For example, we use an information literacy self-assessment quiz (designed by Moira Bent) to encourage students to rate their competencies before embarking on an online course. They can use the feedback given with their results to direct them to particular sections of the online resource. It also gives them a starting point to reflect on at the end of the course too.
One thing I've learnt through developing online resources is not to allow the technology to lead the design. Don't use a technology just because it exists, but because there's a genuine pedagogic need for it and/or it enhances the learning experience.