As Greg Beaver mentions in his latest blog entry, the main website for PEAR, pear.php.net has been mirrored as part of an effort to restructure and "revamp" the PEAR wesbite.

I'm excited to announce the first two mirrors of pear.php.net are now actively mirroring the installer REST files and actual .tgz files of package releases. They are http://us.pear.php.net (provided by Joshua Eichorn and bluga.net) and http://de.pear.php.net (provided by Christian Weiske). The option exists at a future date of mirroring the entire website, but this will not be possible without further changes to the infrastructure.

Using these servers is only slightly different than the main site, setting the preferred_mirror setting in your configuration to use one of the above.

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.

There's a tutorial over on mpwebwizard.com that's been updated and talks about using a mirror to handle hits from a popular website (like digg or slashdot).

caching services such as coral content distribution network provide an alternative for when your site goes down, but why wait until it gets to that stage? why not just send all your hits from high-end websites to the coral cache version? well, there isn't a good reason not to, so i'll show you how to do it automatically.

He provides the simple script that looks for certain sites in the "HTTP_REFERER" value of incoming calls and pushes them off to the cached location with a header() redirect. The whole thing is only 12 lines, not counting the $sites array.