I recently received a request from an advertising company that thought that this site would make a good match to a lot of the advertisers that they had on their books. Their particular advertising doesn't interfere with the other advertising on the page (so they claimed) because all their code does is to convert some of the text content of the page itself into links that display ads when clicked on.
It was at this point that I remembered the hosts file which you can use to speed up the access to sites you visit regularly by providing them with the IP address of the site and so avoiding the need for a domain name search. If a site moves to a different IP address then the entry in the hosts file no longer points to the site and you need to find where the site has moved to to update the entry to point to the new location.
The hosts file can also (perhaps not so obviously) function in reverse to stop your web browser from being able to locate a particular site and hence to avoid wasting time downloading huge files from that site that serve no purpose.
To achieve this all that we need to do is to examine the source code of the page to determine the domain name that the file is being retrieved from (eg. scripts.example.com). We then place an entry into the hosts file specifying an IP address of 127.0.0.1 followed by this domain name. The IP address of 127.0.0.1 always represents the computer it is actually on and so requests for files from that domain will never leave your computer.
Most firewall programs should also provide you with the option to block access to particular sites.
This article written by Stephen Chapman, Felgall Pty Ltd.