[TYPO3-english] Does anybody know where to find the article "The Mysteries of &cHash"?

[Ulrik Høyer Kold]

This article[1] is no longer available at typo3.org.

Where can I find it? Is it in an extension? In another piece of 
documentation?

Do you know where I can read "A must read for every extension author!"?

Have a nice summer!

Sincerely,
Ulrik Høyer Kold, Net Image A/S

[1] http://typo3.org/documentation/article/the-mysteries-of-chash