Some colleagues introduced me to Prezi last fall and I have been hooked on it as a presentation tool ever since. It's a web-based flash program that allows you to use zooming and orientation to design a non-linear stage of ideas. You can still design an order of things you want to show, but visitors can also click around the elements freely.
Prezi has good (free) licensing options for educators and they are constantly improving the features of their application. One of the best features is the ability to copy shared templates from other users who have already put together cool presentations.
Below is a Prezi that I'll be using next week at a conference in Boston.
Header photo by Robert S. Donovan