That's an interesting approach.

Personally, I just use CPAN::Mini (well, actually CPAN::Mini::Devel that includes latest development versions, too) and serve that up on a local webserver on the network. While there is a big one-time hit to synchronize the first time, the ongoing hit on a mirror is fairly minimal (most distributions are pretty small). At this point, disk is cheap, so I figure why not have it all?

If I wanted to only mirror a specific list of modules, I would use the module_filters parameter (which ordinarily filters out a list of modules) and just invert the logic.

  module_filters => [
    sub { $_[0] !~ /Foo::Bar|Baz::Bam|.../ }
  ]
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