Daily, a lot of internet surfers, are bombared with solicitations to enter porn sites. In a recent study from Eblocs, 100 sites were tested and it was found afterwards that- 98 percent of them use some form of Spyware, or Adware, 15 percent of them use porn dialers that send you to other porn sites, 95 percent of them install Spyware/Adware (which later launch pop-up ads) and 5 percent of them install Browser Hijackers.
If they are putting all these things on your computer, there is also the risk for "Phishing/Pharming", where you could become a victim of identity theft. Most of these sites ask for a credit card, or check card of some sort. This information could also be used in credit card fraud.
Here is a earlier posting on "Phishing". Phishing is where a victim is induced by fraud e-mail, or going to a fraudulent site on the internet to give up personal information, which is used in identity theft.
http://fraudwar.blogspot.com/2005/05/phishing-statistics.html
In this country, we are free to view this sort of material, within certain limits. If one chooses to do so, be careful it isn't a front to defraud you of your hard earned money. It might also be wise to have the most updated virus and malware protection on your computer.