The hacker group Cult of the Dead Cow has created Offensive Computing, a malware repository site, inviting security researchers and others to upload infectious software of all description, and maintaining a database that any new piece of badware can be compared against. You can download malware, compare a newly discovered piece of badware against known samples, and so on.
(Thanks, Grandmaster Ratte'!)
Update: Val Smith sez, "One thing to note is that offensive computing is a new group of its own, which is affiliated with cdc. I am the founder of offensive computing."
