Far worse than the program that the Hun is talking about are TopText and Surf+. These companies sell links on your website and don't pay you a penny. They will even go so far as to re-direct all of the existing links on you page to their advertisers. For example, they can sell the top 10 listings on The Hun, or any other site, to any paysite that they want. They are also known to sell adult links on kids sites like Disney.com.
You can see screen captures and find out more info here:
http://www.scumware.com/
These programs destroy your website and blind link the hell out of your visitors. If they are not stopped, then no webmaster will be able to pay for their sites in the future.
If you think this is no big deal, consider this. TopText is distributed with Kazaa. Over 8 million people have downloaded Kazaa already and hundreds of thousands more are downloading it every week.
Again, please check this site out and spread the word:
http://www.scumware.com/