From Fiona Stewart
You report on a Mozilla Firefox browser plug-in called Lightbeam, designed to reveal the numerous websites which grab data when you browse (2 November, p 23).
However, going a step further would be useful. The old firewall program Zone Alarm Professional version 7 could not only detect all these data grabbers, but also allow you to block them. Sadly, subsequent versions omitted this wonderful privacy feature.
London, UK
