In a new post on hsi blog today, John Cox talks about a workflow engine that he's found for PHP - this activity-based one.

An activity based Workflow Engine for PHP not only appears to be a decent workflow engine, but it also gives a great explanation of what workflow is.

Without a workflow system the processing of the component parts has to be handled manually, which is where mistakes can occur. Forgetting to charge the customer or ship the order is not a good way to run a business.

It's an interesting take on the structure of a PHP application - this does this, then fires off this, which spawns these two, etc. I could see it being useful for a wide range of applications, including the obvious ecommerce sites...