Here's an ipfw command to block VeriSign's site finder internet domination plan:
sudo ipfw add deny log all from sitefinder.verisign.com to any in via en0[robg adds: I'm not sure this is the ideal way to prevent the sitefinder takeover, but it works. If you enter an unclaimed URL, your browser will time out instead of loading VeriSign's page. To remove the rule, use sudo ipfw zero 00100, where 00100 is the rule number that appeared when you entered the rule (you may then have to toggle the firewall on/off to get things back to normal). For more on the Verisign takeover of unused domain names, see the news.com article VeriSign redirects error pages, or visit /. for a couple of additional stories...]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20030916235049812