This is a scam. A friend of mine just posted the recorded conversation with these guys (pretending like he was falling for the scam). It's a good listen if you need a laugh (or to educate yourself not to fall for such scams).
http://soundcloud.com/bartek-kujbida/virus-scam
I just got a call from these guys. Just for fun I went through the steps up to the point where he wanted me to allow remote access to my computer, after that I just shut him down. It was fun stringing him along. Listened to the phone conversation from the previous poster's link, funny as hell.
I just received a call from 3122638166. The other number is 5167469209 He stated I was going to get free grant money. ANd that he needed my credit card number of only $3.87 to get the user id, password so I can get the free money..