&#62; Most of my revenue has been been from virus and malware removal. I coupled the virus/malware removal with an antivirus installation service for $19 and most people gladly paid it.<p>Once a computer has become infected, it's fairly impossible to determine if the infection has been completely eradicated.[1]  I wonder that that $19 buys you.  A few executions of anti-malware software until they claim "Clean"?<p>[1] I realize that even in the absence of a known infection it's "impossible" to know whether you're infected.