This week a disturbing report was shown to me. A virus or worm known as DNSchanger was reported by the FBI to have infected computers over the last two years. A group of Estonian hackers infected hundreds or thousands of computers with a computer virus, this virus will redirect certain calls to websites like Apple, Microsoft, etc. Because this virus alters the way the DNS system works on computers, all systems are possibly infected, this includes, but is not limited to, Windows, Macintosh, and Linux computers.
Here is a link to the article in which I found out about the virus http://www.myfoxdetroit.com/dpp/news/national/hundreds-of-thousands-may-lose-internet-in-july-20120420-ms
There are a few websites you can go to from various security firms. One website is http://www.dcwg.org/detect/ this website contains a list of different websites, in different languages, I have visited every single website in this list and can very find that they are all clean and will not infect your computer.