Have you run Windows Update since Thursday (if you use a PC)? If not, make sure you install the patch Microsoft just put out. Easiest way is to just run Windows Update. They found some big gaping hole in Windows that allows hackers to infect your system just by you loading the wrong image file from a website, e-mail, wherever. Microsoft put out a patch on Thursday, so make sure you're all safe and stuff. This concludes your public service message.
