CIO.com has an article about a new type of invisible rootkit.
"Security researchers have discovered a new type of rootkit they believe will greatly increase the difficulty of detecting and removing malicious code.
The rootkit in question, called Backdoor.Rustock.A by Symantec and Mailbot.AZ by F-Secure, uses advanced techniques to avoid detection by most rootkit detectors."
A rootkit, is a type of malicious program that allows someone to conceal that they have taken over your computer. Rootkits are very difficult to find, and this new method is even more sophisticated.
As usual, using a Linux live CD will bypass all possible rootkits that may be running on public computers.