One of the sites I like to go to often and one that will no doubt get a large amount of traffic over the next few months is Common Craft. I especially love the way the use video to explain difficult or complex issues. They did a great job on explaining social media.
They have recently released a new video on the complex term of cloud computing. This video is another great example of explaining things to people like your grandmother, or me for that matter, issues related to what would normally only be understood by those in the field or the cool smart kids.