If you just look at the link, it won't make much sense. But if you view the coding (listed as View Source on most browsers), you'll see what designer Evan Roth has wrought. The webpage consists of a single sentence nested inside every HTML tag in alphabetical order. And that sentence is, appropriately "One sentence contained within every HTML tag in alphabetical order."
Link -via
Kottke | Photo by Flickr user
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Previously by Evan Roth:
Graffiti Taxonomy
I think it's cheating that he commented out some tags.
The correct spelling for "non-depriciated" is "non-deprecated".