According to the FBI, cybercrime complaints rose 20 percent in 2009, and victims lost $559 million, more than double the year before.
With online crime on the rise, it's more important than ever to protect your systems. But you don't have to pay a lot of money for security. The open source community continues to produce (and maintain) excellent tools that fulfill a wide variety of security
To see the list,check: http://itmanagement.earthweb.com