are there any viruses that effect linux

[mike]

Hi, as far as I know there are very few viruses in Linux. But I had a strange thing happen. I installed ubuntu for a friend, and she called me a few days later and said she was seeing a update notice.
I think this was on a sight, because she clicked one and it then said the system was infected and kept wanting to install software. I new right away there was no problem when she red to me some of the files it said were infected, because they don't even exist in ubuntu. Then the program stated it was a windows program, so I had her re start the computer and everything was fine. The sight she was on was verizon. She checked the ubuntu updates and saw there were none. Have any of you ever run into anything like this?
Mike.