McAfee SiteAdvisor for Firefox 26.6

Even the most advanced antispyware security can't guarantee your computer's safety, because most programs scan your site for digital nasties after they've already taken root. This ingenious Firefox extension warns you about covert spyware and browser-hijack attempts as you visit a site.

SiteAdvisor operates as an unobtrusive signal in your browser interface, turning green if the site is safe, yellow if it's suspect, and red if it senses threats or annoyances. The same coding system applies to Yahoo and Google search results, inserting a red, yellow, or green icon next to each link. Clicking these icons provides full diagnostics of the sites' threats, including links to other suspect sites, high spam counts, and the number of dangerous downloads.

We also liked the URL highlighter, which displays site rankings directly from your search engine, helping deflect drive-by installs that may initiate as soon as you type a URL. In our tests, SiteAdvisor turned out accurate and reliable results, and though it doesn't have a wide array of features, we urge any regular Firefox user to try this no-cost extension.