Read on Feedster: new variant of the Sobig worm appears. Yesterday I got a mail from "System Administrator" titled "Your mail could not be delivered" with a completely unknown receiver mail address and an attachment. Clear that I have not opened the mail. Especially wondering about that message itself: have not send any message within the last 3 days (weekend). Also received some of the messages from support[at]microsoft.com which are reported to be virus last week. Spam-/Virus is filtered here by a server side running antivirus software (also my GMX account now filters) and on the client Cloudmark also helps.
But the best workaround to not open malicious mails in Outlook/OE is to disable the preview pane and enable the auto-preview for the Inbox folder. This way I can read over the first three lines of the message, display the mail header (Right-Click-Options) and then press "Block", the Cloudmark plugin button to move the mail to the Spam folder where they are deleted every 3 days. Missing /dev/null on my machine ...

Found on Harry Pierson aka DevHawk: PowerToys for VS.NET 2003. What I have missed a long time: the Custom Help Builder. Thanks for the links!