I've got a dump of the wordpress codex available as a single zip file at
The content was obtained from the codex on 12 Feb 2007.
The reasons for this are explained very nicely at http://www.tamba2.org.uk/T2/codex-and-pdf/
Also, I personally believe that there are a lot of dial-up or simialr limited access users who would like to have one Codex download at a specified time and then peaceful offline browsing of the codex.
Megashares or such other file sharing service seems to me to be good enough for this, but if anyone wants to go ahead and
1) host his own mirror,
2) mirror this at another file store, but with a nicer url
3) start a sourceforge project for this download
4) make a global-to-local Codex synchronization plugin(!!),
I'm as happy as anyone else. Feel free to ask for help, but no guarantees that you'll get it :-) (i'm pretty new around WP)