I had to leave my laptop with a pc doctor today after getting hit with a trojan called Windows Recovery. It tries to make you think you have problems with your hard drive and you get a black screen with a window offering a scan and then tells you you need to pay for an advanced version to get rid of the problems it finds. Do not follow the link and pay with your credit card or you will be screwed. I dont know which site it was I picked it up on but it wasn't here.
Just letting you all know in case you come accross it. I use Firefox browser instead of internet Explorer and in 4 years never had a problem. Guess it's time to renew my virus subscription.