When I tweeted a review of Andreas Glaeser’s book yesterday that I had read on orgtheory.net a friend retweeted the post and added that “it’s only $8.55 on kindle”. Since I new the book was priced at £18.17 on amazon.co.uk I looked up the amazon.com site with my iPhone and noticed that it showed me a price of $29.10.

When arriving home I checked the book on my laptop and found a difference in price when I looked into the amazon.com site from when I was not logged in.

When logged into Amazon.com the price was $29.10.

When I log out of my account and search for the book again, the price goes down to $8.55.

This observation points wither to personalized pricing or to big differences in geographical pricing of books and probably other items. In any case it reminds me of the advice that Eli Pariser gives in his book an on his website The Filter Bubble, clean your cookies.