On the Zend Developer Zone, there's a new article concerning the creation of zip files and tarballs inside of a PHP script, including a link to a tutorial from PHPit.net and the steps he had to follow to get started.
Who hasn't sat in front of their computer night after night wondering aloud - to only the monitor and the voices in their head - how they are going to build a zip file or tar ball dynamically using nothing more than PHP. I know that if I had actually thought this, it would have kept me up at nights. Thankfully, before it got that far, those wacky code monkeys over at PHPit have come up with a tutorial that walks you through just this very conundrum.
He noticed he didn't have the packages he needed (Archive_Zip is still "beta"), so he had to issue a pear install to grab it specifically. He comments on the usefulness of parts of the tutorial (examples vs. explainations) as well as the choice to go with a reusable function instead of a wrapper/helper class around the PEAR package.