Magento Events and Observers, practical example

Hi guys and girls. I wrote a new article at Inchoo.

We have a client that has a specific request that requires extending the default Order object. In the article I go trough process of adding new attributes (properties) to object (that can be saved in database) via $object->save() method. Plus, you have an example of how to hook (observe) event and do some useful stuff.

Hope you find it useful in terms of event driven programming (hooks) in Magento.