Blocking Unwanted Parasites with a Hosts File
You can use a HOSTS file to block ads, banners, 3rd party Cookies, 3rd party page counters, web bugs, and even most hijackers. This is accomplished by blocking the connection(s) that supplies these little gems.
Example - the following entry 127.0.0.1 ad.doubleclick.net blocks all files supplied by that DoubleClick Server to the web page you are viewing. This also prevents the server from tracking your movements. Why? ... because in certain cases "Ad Servers" like Doubleclick (and many others) will try to open a separate connection on the webpage you are viewing. For XP SP2 users you should see a Security Center prompt about allowing this connection. screenshot Simply click No and continue. Yes the prompts can be annoying but at least you'll know, however you should not see these prompts if these entries are included in the HOSTS file. Note: this prompt only occurs if (example) *.doubleclick.net is included in the "Restricted Zone".
Thanks to Randy Knobloch (aka: Siljaline) and others for providing the online update notices for the HOSTS file. These updates are posted to most major security related sites, Newsgroups, and mailing lists.