Adding visual elements (such as pictures, maps, or charts) can really enhance your speech.
Use Creative Commons Search to search different providers for items that are specifically licensed under a CC license. For information about copyright restrictions, see the Copyright and Intellectual Property Toolkit: Can I Use It? guide.
Search Google for pictures, maps, or other visuals to supplement your speech. Tip: You can also try an Advanced Google Image Search. By selecting "Labled for Reuse" in the Usage Rights drop-down box, you'll ensure the images you use are not violating copyright licenses.
Wordle is a free site that lets you input text (such as President Obama's acceptance speech, seen below) and generate a "word cloud." Words appearing more frequently receive greater prominence in the cloud.