Does your Windows PC have too much fun when you’re not around, cavorting on the Internet, guided by rootkits you know nothing about? If your Windows PC runs uncharacteristically slow, it might be serving a network of bots controlled by criminal hackers who use the network to make considerable profits in click-through schemes and spam delivery.

The Sony BMG rootkit fiasco continues to haunt the PC industry as Sony BMG tries to settle the lawsuits. Researchers note that the Sony BMG rootkit affected more than half a million computers. More importantly, the tools and information to develop custom rootkits are freely available and thieves are wiser about how to use them.

According to “Rootkit numbers rocketing up, McAfee says” by By Dawn Kawamoto of CNET News.com:

In the first quarter, the number of rootkits seen by McAfee’s Avert Labs grew by 700 percent, compared with the same period last year… While Microsoft’s Windows is the main target of malicious rootkits because of its high level of use, McAfee also noted that its many undocumented application programming interfaces (APIs) make it an attractive target.

A rootkit’s purpose is to hide code — adware, spyware, or the latest threat, botware that turns Windows PCs into zombies. According to “What’s the next security threat?” by Ron Condon of CNET News.com:

The spyware or Trojan horses they plant on unsuspecting users’ machines do not draw attention to themselves, but once installed, they work as slaves to their remote masters. Users are rarely aware that their machines have been hijacked. The system continues to work, albeit slightly more slowly at times, and they have no control over the secret tasks it is being asked to perform. Bot networks, which are armies of these hijacked computers, have become the predominant feature of the Internet threat landscape. According to security company CipherTrust, more than 180,000 PCs are turned into zombies every day, and that figure is continually rising.

What can you do about this? You can attempt to remove any rootkits from your Windows system — try F-Secure BlackLight, or Microsoft’s Malicious Software Removal Tool, which according to eWeek has been recently updated to detect a few notorious rootkit-makers. Good luck with that.

Of course, I prefer the Microsoft Software Removal Tool, which is designed to remove all traces of Microsoft software from your life and provide a measure of computing diversity in the networked world.