Web companies can track you -- and price-gouge you -- based on your battery life
by Cory Doctorow from on (#1PPD7)
In Online tracking: A 1-million-site measurement and analysis, eminent Princeton security researchers Steven Englehardt and Arvind Narayanan document the use of device battery levels -- accessible both through mobile platform APIs and HTML5 calls -- to track and identify users who are blocking cookies and other methods of tracking. (more")