This extension offers a PHP interface to the YAZ toolkit that implements the Z39.50 Protocol for Information Retrieval. With this extension you can easily implement a Z39.50 origin (client) that searches or scans Z39.50 targets (servers) in parallel.
The module hides most of the complexity of Z39.50 so it should be fairly easy to use. It supports persistent stateless connections very similar to those offered by the various RDB APIs that are available for PHP. This means that sessions are stateless but shared among users, thus saving the connect and initialize phase steps in most cases.
Clearly, if I wasn’t so lazy, I’d get around to compiling YAZ into my PHP and actually build something with it. Though without Z39.50 on my own ILS, the incentive is understandably diminished.
Finally, I’ve gotten an answer about indexing cat dates in III so they can be used in searches or sorts. The answer is mostly “no,” but I go into a little more detail at LibDev.