It's not secret. The master list is Matt Drudge.
I thought it was the RNC blast fax. Do you remember how Atrios weaseled his way into a passcode for the RNC post-debate conference calls?
I do remember that. But if it were just a blast fax, wouldn't some unintended recipient have seen it yet? I've never heard of someone seeing and leaking it.
The book/movie _The Puppet Masters_ may answer the question for you.
I wrote about this back in March, 2002, here, and again in January of 2003 lamenting that no one had linked.
On a related note: lots of posts yesterday, finally.