|Symantec Security Check - FREE scanning your computer for exposure to hackers and other online threats
Trend Micro™ HouseCall - FREE on-demand service scanning your PC for viruses, spyware, and more.
Sygate Online Service - FREE scan your computer for open port/door that may invite hackers to visit your computer.
Audit My PC - FREE firewall test and other services
http://www.insecure.org/tools.html - top 75 network security tools
http://www.us-cert.gov - Established in 2003 to protect the nation's Internet infrastructure, US-CERT coordinates defense against and responses to cyber attacks across the nation.
http://csrc.nist.gov - National Institute of Standards and Technology
http://www.treachery.net - a clearinghouse of security-related information by which system and network administrators may better defend the systems for which they are responsible
Security Check Lists - check list to secure servers, desktops and other