Spyware: Consumer Reports found 545,000 households had to replace computers in the past six months and one in 12 people had serious problems with spyware.

Online identity theft: Consumer Reports estimates 1.7 million households were victims of ID theft committed over the Internet in the past year, of those two-thirds said the incident occurred because of an online purchase.

Certain online threats are almost as prevalent today as when Consumer Reports conducted its first survey five years ago. Consistent with last year's findings, 1 in 3 respondents had heavy levels of spam and 1 in 7 have had serious problems with viruses.

Security Software: Free Software Programs Match the Best Pay Products Consumer Reports State of the Net survey found that 35 percent of U.S. households didn't use software to guard against inadvertently downloading "badware," and 18 percent didn't use a program to block potentially destructive online viruses. Cost should not be a concern to have an unprotected computer.

Through testing, Consumer Reports found that free programs available to protect against viruses, badware, and unwanted spam were on par with the best pay suites tested.

Of the seven free programs Consumer Reports tested this year, the top three no-cost performers from last year performed the best again: Avira AntiVir Antivirus Personal, Microsoft Windows Defender and Spamfighter Standard. What's more, each was better than their former version.

For maximum antivirus protection, Consumer Reports recommends the Eset Smart Security, $90, as well as the features-packed McAfee Internet Security, $70, and the Symantec Norton Internet Security, $60, for its ability to detect badware and provide information about those threats.

When looking to select a security system, Consumer Reports suggests the following guidelines:

Assess your security practices. Determine the practices used on the computer to best provide protection. Consumer Reports free "suite" and pay suites -- except for the four at the bottom of the Ratings -- provide ample protection if consumers are surfing safely.

Consider your computer. Look at the computer's operating system to see how susceptible it is to viruses. While Apple computers may be less likely than PCs to be attacked by viruses and spyware, they can still transmit infected files to Windows PCs. Added antivirus protection should be considered.

Stand-alone software vs. suites. While the three, free stand-alone software that were tested can act as a makeshift suite; they create some inconveniences when used together. Tests showed they can cause the PC to run slower at times, the Avira antivirus program pops up a promotional box when it updates, and Spamfighter adds an advertising message as a footer in all out-going mail. Conversely, a pay suite can be simpler to use and less costly than using multiple stand-alone commercial programs, adaptable to as many as three computers in the same household and might offer features stand-alones don't possess.

Consider support. Consumers should evaluate the tech support needed for the software as free programs usually come with limited assistance and most of the tested pay suites offer free e-mail and chat support. Consumer Reports cannot comment on the quality of any program's tech support.

Add other protection. Even though some operating systems have built-in firewalls, additional protection may be needed. Consumer Reports recommends adding phishing protection (especially when using an older browser version) such as the McAfee Site Advisor or the Netcraft Toolbar. Other worthwhile free additions include the ZoneAlarm firewall and the Eraser file shredder.

The latest issue of Consumer Reports also includes Ratings on 31 laptop, 27 desktop, and six netbook computers. The report also includes a look back on a year of online threats and an investigation into corporate and federal culpability in cyberspace. For more information on the State of the Net survey and the entire computer protection package, check out the June issue of Consumer Reports or visit www.ConsumerReports.org. The Consumer Reports' 2009 "State of the Net" survey was conducted by the Consumer Reports National Research Center using a nationally representative sample of more than 2,000 households with Internet access.