tons of ways to stop unwanted advertisements. trick your box into thinking that the offending website is somewhere it isn't. use the hosts file, remap crap to localhost, done. uhmmm almost. actually you'll need this website to do it on mac os x since darwin likes it's netinfo database. (cached here for your pleasure)

now tons of requests get sent to your localmachine... even causing unending errors in netscape. time to start apache and set the errordocument to a blank site. now done. mac os x is great for this since it's got mad bsd skills, though the whole netinfo thing really screws with me.

after adding all naughty crap ad sites to your hosts file or database, you need to change this line in httpd.conf and start apache:
ErrorDocument 404 /errordoc.html

then add this file in your webroot /htdocs/errordoc.html