Sure, you can safeguard your PC with various freeware security apps, but there's something to be said for having a single program that protects you from viruses, spyware, phishing, hackers, and so on. Microsoft's Windows Live OneCare 2.0 is such a program, and Amazon has it on sale for $30--minus a $30 mail-in rebate. Shipping is free, bringing the grand total to zero dollars.
Windows Live OneCare 2.0 (wow, what an embarrassingly bad name) combines real-time anti-virus, anti-spyware, and anti-phishing tools with a managed firewall, a data backup utility, and system optimization. You can protect up to three PCs (Windows XP and Vista only) and get unlimited tech support via phone, e-mail, or chat. (That's arguably the key reason to choose a commercial security suite over a batch of freebies, which tend to come with little or no support.)
Renewing your OneCare subscription will run you $50 annually, so what you're really getting here is the first year free. I'm disappointed that the backup utility doesn't include an online option (why not link OneCare with Windows Live SkyDrive, Microsoft?), but otherwise this is a solid, extremely user-friendly security suite. (I'm basing that on a review of the 1.0 version I did many moons ago.)
The rebate deal is good until June 21, so you've got time to weigh the pros and cons. In fact, you can download the 90-day trial version if you want to take OneCare for a spin before ordering.