Couple of days back I wrote an article on Supplementary Skills for Social Media. Here is a company that provides just that kind of supplementary help - content for Social Media.
Common Craft makes videos which clearly explain stuff! For eg, 'What is Social Media' video. They have quite a few topics on Twitter, RSS, Cloud Computing and more..
I checked the rates, they seemed more at first but then I looked at the individual option, which lets a lone individual like me who wants to use it in her presentations cost just $20 for 3 years which is pretty ok!
So as I was mentioning I think that for a good social media strategy there should be collaboration of such ventures.
They have a link that takes you to a bunch of other companies that make custom videos based on a companies products, ideas or service!