The message about website closures made me think of The Wayback Machine http://www.archive.org/web/web.php as you will still be able to access them there once they have gone (though of course they won't be updated any more).
Some time back, I think someone posted the humorous item about the internet archaeologists of the near future discovering the ruins of the Friendster civilisation, complete with abandoned profiles. The same could have been said of Geocities.
So, could you have an archaeology of the internet? How would you go about it? I guess you could chart the rise and fall of various websites, and how they over-reached themselves in the quest for users (Geocities), or added too many new features (Facebook). This process might be analogous to the rise and fall of empires (Roman, Byzantine, Sasanian...)