Friday just as I was leaving work, one of the users got hit with over 3000 copies of sobig.f - he said 'I was gonna open one up just to see what it was, but I figured I should tell you first.'
Here is the insidious part of this new incarnation of sobig : The 3000 copies of it that the user got were from other people, unknown people, and were discarded out of hand. The 85 copies that actually showed up in his inbox instead of being filtered into the trash were from HIM. So he got 80+ messages with 5-6 different subjects and attachments, all to him from him, and several of those had the appearance of bounce messages from mail servers saying that his email had bounced and he needed to read the attachment to see why. Nasty.
If you get ANY email with an attachment, DON'T OPEN IT. Even if you know the sender, even if it looks like it came from a mail server. It's just not worth it! Even if you end up not reading the latest joke or funny picture of the day, it's not worth it! If you think your friend sent you a funny screensaver, click on it, and infect your home computer, which then sends thousands of emails to all your friends, or even worse, all of your coworkers and you end up being the starting point for a network shutdown that YOU caused at work - well, that is a Bad Thing. Don't open attachments.
And better still, don't USE attachments. If you need to send someone a file, send them an email FIRST that lets them know it is coming, and only then send it. Stop sending jokes and such as attachments. If it's not worth your time to cut and paste it into the body of the email itself, it's probably not worth reading in the first place. We all have to be more careful - there are a lot of really bored people trying to ruin your day with these viruses and worms.