The Economist argues in this article how online services which provide for personalised services are breaching some age-old notions of privacy. Google mines the data it collects from users for two purposes. One is to improve the user experience, making its various online services more personal, useful and rewarding for the individual—and thereby increasing their popularity. The other purpose is to provide better targeted information for advertisers. That is fine for the vast majority of internet users, who are happy to trade a measure of privacy for the convenience. However, most people (though not all) stop short of blurting out more intimate details about their private lives. Even so, all those innocuous bits of self-revelation can be pieced together, jig-saw fashion, by intelligent algorithms. Throw in the digital paper-trails stashed in Google searches and Amazon purchases, and things can begin to get a little scary. The above is a foregone conclusion - we all are ignorin...