mirroring for installs

[Steve Drees]

> Mirroring the entire archive would use more resources (both yours and
> ours) than duplicating the few downloads which occur during the
> installation; I recommend against it.


What about using apt-proxy? I've not tested it with ubuntu, but use it for
all of our debian based servers here and it seems like a lightweight
mirroring solution, especially if you are doing many concurrent similiar
hardware installs.