Ghostery is a FireFox Add-on that analyzes the page you're on and shows you if it contains any trackers ("web bugs"), including advertising, behavioral targeting and web analytic services.
The number one request I've received from Ghostery users is the ability to block the trackers that it detects. Starting with version 2.0 Ghostery allows you to select which trackers you'd like to block or to always block all trackers it finds.
Here are some screenshots of the new blocking function within Ghostery:
You can find full details on what's new in 2.0 here.
Also if you're really interested in Ghostery, Privacy and/or Security you can listen to an interview I did last week about Ghostery 2.0 on the Data Security Podcast here.
A special thank you to Jon Pierce, a friend and local entrepreneur who contributed all the code that behind the new TrackerBlock feature.
Please let me know how I can make Ghostery better. Also if you do find it at all useful please consider leaving a review for it on the Firefox site.