If you see any incoming mail with a file attached from an unknown you simply click the delete button to send it on it's way! Apparently the "Conficker" is an I-Worm type generally seen as an attached file for that type.
Several systems infected produce what's called a "botnet" apparently used to steal personal and other information. One infected system generates email to forward copies to the contacts/address book lists.
"Small but Sophisticated
"The vast majority of threats we see today are attempts to steal confidential information. We know there's a large underground economy where personal information is sold," said Dean Turner of the online security firm Symantec." http://abcnews.go.com/Technology/sto...7163685&page=1