Prezi is a new tool to create stunning presentations. It's free for teachers and students and it's really easy to use. I have done this one about the Passive Voice in just a few minutes This is just a demo to show you that everybody can create new presentations. have a look and try to use it , it's worth.
You can watch it screen by screen just clicking on the arrow at the bottom or use the auto play in full screen, clicking on "more" at the bottom right corner.
Go to http://prezi.com/ to register and create your own presentation.