I have never heard of the site much less the online tool Prezi until my teacher put it as a link on the assignment that is responsible for the debriefing (aka this blog post).
I loved this prezi after searching for Library on the site. Its fun, informational, and completely held my attention.
Essentially Prezi is an online presentation creater. It takes powerpoint to the extreme and adds a lot more demension and intrigue. It takes you step by step through the process of creating a presentation which looks awesome and keeps your viewers attention. There are a variety of templates which are offered for free.
I think that it would be a very interesting tool to use in a library setting and anywhere you need to make a presentation.