We drop Avast on ALL computers that come in, while simultaneously telling every single customer that it will do nothing to prevent them from brand new threats…and neither will anything else on the market today!  Quoting myself, “viruses are a cat-and-mouse game, and antivirus vendors are always the cat doing the chasing.”  Software firewalls are also junk, because any virus that does take root can easily bypass such a program.  In reality, the only two things that are needed to keep a secure network are (A) a hardware firewall between you and the Internet and (B) well-educated, cautious, skeptical users.  Education seems to fly out the window when an erection or free music is involved, which is why 90% of what we see is porn seekers downloading whatever they think will be porn (and obviously wasn’t) and teens who grab LimeWire and proceed to download every virus known to man in the process.  Computers and their software stopped being the weakest link over a decade ago.  The most commonly exploited security hole on a computer is the device which sits between the keyboard and the chair, not the IP stack or WMF rendering libraries.