not much. my first line of defense is me, Chrome and UAC at max. Chrome protects me from drive-by malware and i don't expect to get drunk enough to install malware myself. UAC protects Program Files and Windows folders and reduce the Integrity Level for that 'limited' admin account. my second line of defense is on-demand scanners: Hitman Pro, VirusTotal and sometimes Jotti. anything that i download and that is not from a major publisher is scanned. i only make exceptions for Adobe, Microsoft, NVdia. stuff like that. my third line of defense is Look and Stop Firewall and Password Depot. i don't think i really need any of those 2 but i like the convenience factor. if the ~ Snipped as per TOS ~ was to hit the fan big time, restoring a disk image with IFW would fix the problem. unless i were to get a BIOS/hardware virus or something really nasty. i've been doing this for almost 6 months without a problem. i've even tried to get deliberately infected by drive-by malwares, surfing virus sites for hours. nothing got through i'm glad to say. this strategy would not work for everyone but it works for me. i'm the only one using this computer, so that makes a big difference. i only have 1 user to worry about.