Starting in 1996, Alexa Internet has been donating their crawl data to the Internet Archive. Flowing in every day, these data are added to the Wayback Machine after an embargo period.
Thanks to Sascha Schmitz, Paco Vidarte, Bart Buseyne, Tom Keenan, Lewis Fried, as well as to all those who emailed me over the years with feedback. (Check out the annual reports on www.krapp.org for details...) If you spot mistakes or know of items missing, please alert me by email.