Webroot has released a report, entitled "State of Spyware", in which it claims that 88 percent of all PCs are infected with some kind of spyware or another. The results were derived at after more than one million consumer PCs and 35,000 corporate systems were studied.

Spyware has apparently become big business, with estimated revenues at $2 billion, which represents 25 percent of all Internet advertising revenues. And it's everywhere!

According to Webroot, 88 percent of PCs were infected by spyware during the first three months of this year, down slightly from 92 percent in the prior quarter. The average PC revealed 25 infections, about 18 cookies and seven applications such as adware, system monitors, keyloggers or trojan horses. The company found that 4294 websites and 89806 web pages carried spyware and potentially could infect PCs.

The most common threats of this type were reported to be Cool Web Search (appeared in 107 variants and was found on 8.2 percent of PCs), Gator (present in 2.2 percent) with 180Search (at 2.0 percent) and Powerscan (at 1.8).