My computer is running really slow. I suppose there are a few possible reasons, but I always wonder about viruses. My brother in law told me he got a new antivirus and it reported a worm he had previously not seen.
CNET (an independent ranking agency) lists their picks for antivirus.
Trend Micro PC-cillin Internet Security 2006
from Trend Micro 7.8 out of 10 7.8
Kaspersky Internet Security 6
from Kaspersky Labs 7.3 out of 10 7.3
F-Secure Internet Security 2006
from F-Secure 7.3 out of 10 7.3
CA eTrust EZ Antivirus 7.1
from Computer Associates 6.5 out of 10 6.5
McAfee VirusScan 2006
from McAfee 6.0 out of 10 6.0
AVG Anti-Virus 7.1 Professional Single Edition
from Grisoft 5.8 out of 10 5.8