Well, I'm not too sure about "safe" malware but you can check out :

http://www.offensivecomputing.net/  - it's a database of user submitted malware.

https://www.frame4.net/mdpro/index.php - Similar sort of thing but you have to pay for full access otherwise it's a limited free access.

I normally grab various malware variants from these sites when I need to analyze their behavior, etc... 

Your best option might be to build a small vmware network and make sure its not connected to the internet when demoing a bots or worms that don't require user interaction to spread. Most of the newer malware is smart enough to detect a VM environment though and will change their behavior accordingly so this might limit your demonstrations.

dean

Thanks for the links. Unfortunately I asked about setting up a VM environment and because it is a shared lab and not secure the powers that be will not allow it.

I found a couple of testers with sigs that anti virus will alert on and show how they can work if it was a real virus. I may have to be satisfied with that and just show the code of some that were caught in the wild.

I appreciate the suggestions but as I said I can't setup a VM network or bring any kind of LIVE malware into the school.

What I am looking for is more on the order of a simulator virus - one that mimics a live virus but has no destructive payload.