The InternetArchive archives some pages of the Internet and makes them available to the public. Although the coverage is far from complete you can sometimes observe the development or evolution of pages over time.

Another benefit is that you are able to see pages like the EbolaPage, which are talked about but offline. Now you can go and have a look at these pages. 

The URL for the InternetArchive is http://www.archive.org/

See WaybackMachine or look at the history of this page on waybackmachine.org:
http://waybackmachine.org/*/http://c2.com/cgi/wiki?InternetArchive

The InternetArchive is also scanning books and enabling digital book lending. Borrow digital books here: http://openlibrary.org/

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Q: I seem to get only text data from pages retrieved via InternetArchive, e.g http://web.archive.org/web/20010304032426/http://www.objective.co.uk/events/presentation/9710_java_design/img021.GIF is not found. Is it universally true that images are stripped off?

A: Images are not stripped off. There are many reasons why those images may not be available in the archive. For instance, the crawl that gathered the content was terminated before the requests for the images were made; perhaps incomplete data was donated; perhaps the path to those images is disallowed by the site's robots.txt. Waybackmachine.org now goes to the "live" web for requests that are not in the archive, so this problem should happen less.