Download: Avast AntiVirus 4 (Size: 29.9 MB)
Avast is the best antivirus in terms of resource consumption. It has a low CPU and memory footprint, even while scanning. Several independent tests have found out that Avast is comparable to Norton Antivirus, Kaspersky etc. in terms of scanning accuracy, quicker than every other antivirus, and has the smallest online updates among them. Virus definition updates often go unnoticed, and we are alerted only when the update is complete.
Currently at version 4, and free for home use.