Wayback Machine: Now with 240,000,000,000 URLs – the web archive now covers from late 1996 to Dec 9, 2012. If you don’t know about this great resource already, the Wayback Machine is part of the Internet Archive.
The Internet Archive’s Wayback Machine is a service that allows people to visit archived versions of Web sites. Visitors to the Wayback Machine can type in a URL, select a date range, and then begin surfing on an archived version of the Web. Imagine surfing circa 1999 and looking at all the Y2K hype, or revisiting an older version of your favorite Web site.