I'm a sucker for successful communication whether it be visual, written, or oral. So take a look at this presentation from Scott Gavin titled "What is Enterprise 2.0"? It uses a persona based approach to tell a story. The story resonates (well it does with me anyway). There are millions of people who work and live just like Charlie. There are also millions of people that work alongside of Charlie who may do things very differently than he does.
This helps us think about those differences and makes us ask ourselves—"what would Charlie do"?
Now someone needs to do a version of this presentation that reflects how Charlie's boss works—and let's give the poor guy a name shall we? ;)