Content Management System
At it's core, websites are made up of 2 parts: the content (including text and images) and the layout. To edit content on flat, non-dynamic sites clients would have access to all the code of the page. Forget to close a single div tag and everything could break.
Content management systems separate content and layouts by using databases and templates. The content - editable via a backend admin site - is saved in a database. The layout - with all the html and php code - builds the pages based on the design and pulls in the content.
BBS Real Estate Brokerage
Oh this site was fun! They originally wanted to keep updating their data on a 3rd party site (why?) so I had to write php script that would parse through the html generated search results to get all the property info. My script also had to save the info in Expression Engine preserving things like categories and relationships. It wasn't easy but I won in the end.
Buds Spas & Pools
The Home Staging Studio
Greenway Home Products
Mudpies and Daisies
Bebe Dahl - Sheikh Shack Show Studios
This site also has a dynamic registration page for travel to meetings, etc. Based on the username/password the user is directed to a specific subset of documents for that specific destination. This fun little bit of coding was done without modifying any of the cmsms core code. These cms' are pretty powerful if you know how to bend it to your will.