Visualization is key.
Your knowledge is only as powerful and important as your ability to share it. And to be effective, you have to know how to capture your audiences's attention.
This video reminded me something very important today. Re-taught me, to tell you the truth. I always believed in the power of usability, visualization and aesthetics as means of communication.
You have doubts? Take a look. You can visualize how truthful my words are :)