Thinking about security in today's computing world is vital. Everyone needs to be concerned about viruses, firewalls, spyware, and spam. Users with broadband Internet access and Wi-Fi have additional worries. But most of us don't have the resources or the time to construct elaborate software and hardware obstacles. With those limitations in mind, we'll identify some creative ways to keep your home or small business computers secure without breaking the bank.

Protection Up Front

Start with software. The first word in security software is always "antivirus." Symantec's Norton AntiVirus ($39.99) and McAfee's VirusScan ($39.99) are the best-known products, but Comodo (free) and Grisoft (free) offer free basic antivirus applications, though with some limitations. The more established (fee-based) programs tend to be more reliable and provide broader protection than free products, and they aren't very expensive. In any case, virus protection is essential regardless of your budget.

Next, run a firewall program. Firewalls monitor network traffic for suspicious activity, hide ports from potential intruders, and block unwanted connections. One of the best firewall products on the market, ZoneAlarm (free), has the best price around. The professional edition costs just $40, but the freeware version stands strong on its own. Windows XP includes a built-in firewall, which we discuss in our Windows Security Sidebar, but its feature set is limited.

Spyware is the scourge of many a system. Whether programs spawn endless ads or surreptitiously report on your computing habits, spyware is a major threat to any home or office's security. Microsoft stepped into the breach, offering a free antispyware program called Windows Defender (free). It integrates well with XP's security features, runs scheduled scans, and automatically updates. Spybot Search & Destroy (free) is another free antispyware application, and has a better reputation than Windows Defender. Again, you can pay a little (usually less than $30) for robust commercial products like Ad-Aware ($26.95) or Spy Sweeper ($29.95), but Windows Defender at least covers the basics when money's tight.

As anyone who's ever used e-mail knows, spam is a massive problem. It's more than annoying--it's dangerous. You might think you're just dealing with shady "special offers," raunchy come-ons, and dubious schemes.

But a lot of spam carries viruses, Trojan horse applications, or "phishing" attempts disguised as legitimate business correspondence attempting to capture personal or financial information. Outlook, Outlook Express, and most free Web mail services have basic filtering in place, but you ought to explore a dedicated antispam application. Cloudmark Desktop ($39.95) and CA's eTrust Anti-Spam ($29.95) plug into either Outlook or Outlook Express, update definitions based on user feedback, and cost less than $40.

It's certainly possible to combine the best programs from each category and create a low-cost collection of separate applications. Sometimes, though, it's easier (and perhaps cheaper) to invest in a complete security suite. Industry leaders, including Symantec ($69.95), McAfee ($49.95), and Zone Labs ($49.99), all offer comprehensive antivirus, firewall, antispyware, and antispam security packages for under $70.

Be Careful Out There

Though the Internet is the source of many security headaches, it can also be a tremendous resource in keeping home and business computers trouble free. If you want to double-check primary virus scans or are reluctant to pay for an installed antivirus application (though we highly recommend one), there are several reliable online scans. Trend Micro's Housecall scan is the best known, though Panda Software and PC Pitstop offer free online scans as well.

Online scanning isn't limited to antivirus applications. Trend Micro offers a free online version of their Anti-Spyware application as well. Online tools don't provide continual protection or automatic scheduling, but sites are available any time to order up a scan.

Finally, and perhaps most importantly, the Internet is an invaluable resource for testing a system's security. Free scanning tools abound, but your best bet is to rely on established commercial vendors to test firewalls, antispyware tools, and Windows settings for proper configuration. Sygate Online Services and Symantec's Security Check offer extensive free port scans, settings detection, and application testing.

Safety Gear

Home and small office users with broadband Internet access and/or wireless networks have extra security concerns but, also, extra opportunities for secure configuration. First, make sure your broadband modem acts as a firewall and network router, or invest in a separate firewall/router device to sit between your Internet connection and your system. LinkSys and D-Link offer basic routers with firewall capabilities for around $50. Configure the devices for maximum security according to the documentation. In particular, turn off unneeded services and change any default passwords.

Wireless networking gets a bad security rap. Though the technology has inherent limitations, you can do plenty to enhance wireless security. First, turn on encryption at the access point to keep strangers out. Next, follow the manufacturer's instructions to change and then avoid broadcasting your network ID. Use strong passwords, avoid sharing sensitive information wirelessly, and don't be afraid to shut down online devices during long inactive periods.

You don't have to spend thousands on enterprise-grade security or a full-time staff to monitor your entire computing environment. But with just a little savvy, home and small-business users can manage basic security on a budget and still have something left over at the end of the year.

Gregory Anderson is a technology writer based in Philadelphia.

Keeping Windows Safe

Third-party and commercial applications do a great job of managing security. However, several built-in Windows options can help make systems more secure without adding any new software. They aren't enough to make you safe on their own but, together with our other low-cost alternatives, they're an important component to any security plan.

Start with Windows Update. Open Internet Explorer and select Windows Update from the Tools menu. Once at Microsoft's site step through the wizard, then download and install any critical updates. Next, turn on Automatic Updates to make sure your system is getting Windows security patches and bug fixes automatically. In WinXP, right click My Computer and choose Properties from the context menu. Select the Automatic Updates tab and choose the Automatic option.

Disable Remote Desktop and Remote Assistance next, unless you have a specific need for one. In the same System Properties dialog box, select the Remote tab and uncheck the boxes for both options. Next, turn on Windows Firewall. Access the Windows Control Panel and open Security Center. Click the Firewall option and set it to "On" unless you're using other firewall software requiring you to disable Windows Firewall.

Finally, check Internet Explorer's settings to decrease your vulnerability on the Web. Under the Tools menu, select Internet Options. Under the Security tab, make sure the Internet zone's security setting is at least Medium and, under the Privacy tab, set the slider to Medium High (controlling cookie behavior). IE's built-in Pop-Up Blocker (under Internet Options' Privacy tab) can also help contain uninvited browser windows. -- G.A.