At 18:57 28/08/2001, you wrote:
>I've been sitting here trying to checkout my purchases at amazon.com for
>the last 30 minutes now and every time I'm about to log out, some new
>Perl/Apache book catches my eye in the sidebar and I end up adding it to
>my cart too... I hope to be checked out by noon at this rate. :)
>
>Amazon.com uses Perl heavily, but the exact technologies behind their
>unrivaled personalization engine are of course not disclosed.
Actually they disclosed something. You will be interested in these US
patents granted to Amazon.
-US6266649: Collaborative recommendations using item-to-item similarity
mappings
http://www.delphion.com/details?pn=US06266649__
-US6064980: System and methods for collaborative recommendations
http://www.delphion.com/details?pn=US06064980__