SecureAnywhere AntiVirus 2012 is, according to Webroot, "the fastest and lightest virus and spyware protection you can buy".
How fast? The company says that after the initial scan, subsequent system scans typically take around two minutes. And when we tried the program it was even faster, with complete scans taking around 35 seconds. Of course these aren't full system scans - there's only time for SecureAnywhere AntiVirus 2012 to be checking your running processes - but as long as its detection engine is good then that's still enough to keep you safe.
The package really is lightweight, too. Memory use peaked at around 50MB during scanning on our test PC, but when idle could be as little as 2MB. And while SecureAnywhere AntiVirus 2012 needs its share of CPU time, this didn't interfere with other things: you'll probably be able to carry on with other things without even noticing that a scan is taking place.
What's more, as the program is cloud-based, checking your files against a huge malware database on Webroot's servers, it's always up-to-date.
And yet despite the program's lightweight nature, it still manages to cram in plenty of features. So you get real-time protection, on-demand and scheduled scanning, browsing protection, a sandbox, the ability to prevent malware from changing your settings, and more.
Note that you need to register at http://www.webroot.com/customerSupport/trialRegistration.php?trpd=WSAV&loc=USA to get a trial serial code.