McAfee VirusScan 2006 (v10.0.27) nabbed an impressive 95% of adware and spyware in our tests, 99% of all viruses in the AV-Test.org zoo collection tests, and 100% of in-the-wild viruses. McAfee VirusScan has a relatively small install size, at just over 52Mb, and supports Windows XP, 2000, ME, or 98. McAfee now offers daily signature updates - a huge plus from the weekly updates offered in the past. McAfee VirusScan 2006 offers exemplary protection at an affordable price. Pros

AVG Free Edition provides free antivirus protection for Windows XP/2000/NT/ME/98. Installing only 30Mb of files and 4 running processes, AVG Free Edition is the smallest antivirus scanner we've tested and may well be the best choice for an older PC with severely limited system resources. Vendor's Site Pros

AVAST 4 Home Edition provides free antivirus protection for Windows XP/2000/NT/ME/98. The scanner installed just under 40MB and 6 running processes to our Windows XP Pentium 4 test system, taking a slightly bigger toll than other free antivirus scanners, but still well suited for older PCs or those with limited system resources. Vendor's Site Pros

Free antivirus software may be the only option for those on a limited budget. The question, of course, is how well free antivirus software protects your PC, how easy is it to use, and if something goes wrong will you be left out in the cold? The answers may surprise you. This review looks at three free antivirus solutions: AntiVir PersonalEdition Classic, AVAST 4 Home Edition, and AVG Free Edition.

Korean-based Iocell has announced VaccineDrive, a USB drive that includes the Hauri ViRobot antivirus scanner. Iocell uses C2, their own developed operating system. They claim to the be the "World's First Portable Anti-Virus Drive. But the C2 platform wasn't even released until Sep '05, and the VaccineDrive specifically was not released until January 13, 2005. Iocell claims that C2 is 'open platform', but that can be widely interpreted and they offer little insight into what that interpretation might be.

Norton Internet Security 2005 AntiSpyware Edition is an all-in-one security suite that leaves most of the protective decision making for adware and spyware blocking and removal up to the user. One wrong choice and your system may continue to spy on you or dish up ads. It's one hefty product too, consuming over 300Mb and installing 11 services, 3 startup items, 2 Toolbars and 2 BHOs - thus it may be less than ideal for already taxed PCs.

AntiVir PersonalEdition Classic provides free antivirus protection for Windows XP/2000/NT/ME/98. The svelte scanner installed only 34MB and 3 running processes to our Windows XP Pentium 4 test system, making it an excellent option for those with older PCs or limited system resources. Vendor's Site Pros

It's not just viruses that plague today's Internet users. Spyware surreptitiously monitors your computer and Internet use, while adware can bombard your PC with unwanted advertising. Both pose a drain on your bandwidth and can lead to loss of security. Following are a selection of the best dedicated adware and spyware scanning tools to ferret out these often hidden menaces. If you go the standalone route, make sure you back it up with antivirus software and a firewall.

G DATA AntiVirusKit 2005 (AVK) provides a double layer of protection, bundling both the Kaspersky and BitDefender antivirus engines under a single, easy-to-use console. The use of these engines offers an important advantage to AVK.

A public beta of Microsoft AntiSpyware was released on January 6, 2005. Beta software is software that has not been thoroughly tested and may exhibit unexpected behavior ranging from benign inconsistencies (i.e. misspelling in dialog boxes, inability to use certain features, etc.) to serious incompatibilities (i.e. inability to access the Internet, system crashes, etc). Beta software should never be installed on production systems. Participation in the public beta is at your own risk. Tech support is not available.