We've been making a variety of short online presentations so instructors at their convenience can view these and try out bits and pieces in their own teaching. We are also deliberately making these online presentations with varying tools so the instructors can compare and contrast them from the point of view of the audience.
Here is one with some general tips about presentation made with Slideshare. The audio for the presentation was recorded with Audacity. So apart from PowerPoint, all the software used here is freely available and hence this approach is quite accessible to student presentations.
Here is another about peripheral devices (wireless presenter, male at both ends audio cable) made with Adobe Presenter. In this case the Campus has licensed the software, but it still costs about $100. It does have the advantage that the audio is recorded slide by slide so the presentation can be readily updated in the future.
And here is one more on Showcasing Student Work made with Jing Pro and published directly to YouTube.