The Internet Archive discovers and captures web pages through many different web crawls.
At any given time several distinct crawls are running, some for months, and some every day or longer.
View the web archive through the Wayback Machine.
Not only did I LEARN something watching Chris' CNN segment today - i.e., that Safari is available for the PC - but I enjoyed watching his random meanderings prior to going live. He's no John Edwards, and that's probably a good thing.