Pretty nice article by Dan Ariely on cognitive biases benefiting certain commercial entities.

http://dl.dropbox.com/u/5506657/ArielyWired.pdf

I think he (rightly) does not claim these are all intentional, I suspect sufficient trial-and error + testing (used by many of the business he covers) will find some of these (which is relevant to the "super-intelligent companies" meme), though no doubt these can be conscious applications of clever marketing.

There used to be a whole semi-quacky but interesting site that was dedicated (among other things) to commercial conspiracies, many pages dedicated to placement of products in supermarket isles, but that was in the age before delicious, and I can no longer find it. It also had some hacking information and was widely duplicated - appreciate if anyone remembers it.