With all the dangers out there on the web, one must be conscious of malicious code on the websites they visit. Even if you're visiting a reputable website that would never plant malicious code, their users could in comments, forum posts, etc., without anyone's knowledge. Webmasters should both implement measures to prevent malicious users from doing this and check their comments and 3rd party posts regularly for malicious code. Sometimes it doesn't even look malicious at first glance but it could be. For some people though, that just isn't enough assurance that they're safe, and they're right.

Firekeeper is a proactive solution for end-users to prevent themselves from being duped by malicious code such as cross site scripting attacks. Its basically Snort for your web browser and its quite impressive. I've been using it for a few days now and its alerted me to several possible malicious scripts on various websites and allowed me to put them on a blacklist. It uses the a similar rule format that Snort does but its much simpler and anyone can write rules (if you know how). Give this plugin a try, it can't hurt.