Launched in 2009, Security Essentials is free and as effective at protecting a PC as any of the free antivirus programs that have been available for years. False positives are few and far between, thanks to strong malware detection and the ability to distinguish between a dodgy file and one that simply displays unexpected behaviour. Aside from slightly slower than average scanning speeds, Security Essentials is very much the new force to be reckoned with. The runners-up for the Best Free Software award were: Spotify, Google Street View, PC Tools Threatfire and Photoshop.com.
