Joshua Eichorn has posted a quick note about a new addition to the PEAR functionality (with some help from Greg Beaver) - hosting a mirror of the main PEAR channel.

At the moment were only mirroring installer data not the entire website but its a start. Things are still in the testing phase, but the mirror is usable, just run: pear config-set preferred_mirror us.pear.php.net

The update runs every four hours, so thing might be a little out of sync sometimes, but if you're just looking to keep things up-to-date, that's more than enough.