Ideally, that machine would have no network connection (as it would be a prime break-in target), and be reported to via null-modem serial cable only.

CNN: Analysis: Linux security

Would it be a haggard, red-eyed hacker working in a basement somewhere trying to break into your network?

FORBES: Intellectual Property Theft: Beware The Enemy Within

Several companies in the last year have been victims of "toll fraud, " a scheme in which hackers break into a company's VoIP network and sell thousands of dollars worth of long-distance minutes.

FORBES: Magazine Article