SlideShare is the world's largest community for sharing presentations on the web. And it's free.
Terms of service and creative commons
Of course creative commons licences are aslmost tailor-made for such a project and therefor are mentioned in the terms as well:
"Certain Submissions may be provided with, and subject to, other licenses, such as the Creative Commons license, which may affect how you use those Submissions. Users of such Submissions may see the specific licenses referred to, and included via links included, in any such Submission. Submitters who make their Submissions available subject to any such third-party licenses hereby agree to comply with all policies and conditions associated with such use and distribution. For more information about Creative Commons, please check creativecommons.org."
Slides about Creative Commons
One can find different slides about Crewative Commons licences, which normally were made for and used in lctures or speeches. And as you can see below, theses slides can not only be downloaded, spread and remixed, but they can be directly embedded on websites and seen as fullscreen slideshows.
