The blog that I link to in the headline for this blog entry mentions AVG 7.1 has the lowest system resource usage, and says that:
Norton Internet Security 2006 was the worst resource hog, McAfee VirusScan Enterprise 8 was the second worst, but Norton Internet Security 2007 seemed to have improved to the third worst resource hog. Trend Micro PC-cillin AV 2006 was the fourth worst resource hog . . .
Good thing I sell AVG - if you don't have it and want to get it, give me a call. Mention this ad, and I'll throw in a free container of anti-static screen wipes.