Yahoo search to 'battle spyware'

Browser exploits: Sites that can harm a user's computer or install malware simply by visiting the site. Any such sites or pages included in McAfee's data will be removed from search results automatically.

Dangerous downloads: SearchScan will display warnings next to search results for sites that offer potentially dangerous software, such as viruses, spyware or adware.

Unsolicited e-mail: SearchScan will alert users to scanned sites that send unsolicited e-mails or inappropriately share e-mail addresses with third parties.
Viruses, spyware and adware programs are often "hidden" inside innocuous-looking programs such as screensavers and toolbars.