At Schools on the Net and Neon Dreams I produced websites for schools and small businesses, with my primary focus on developing an easy to use content management system to provide customers with the ability to manage their website's content themselves, but without having to be familiar with HTML or CSS.
The CMS has other nice things such as an embedded rich-text-editor (TinyMCE) and uploadable images and files (complete with progress bars), drag-and-drop to place images, to order galleries and to order pages.
Implementation speaking, I developed the content management system in PHP, with MySQL as the database backend. Internally the CMS uses an n-tier architecture inspired by Rails (of Ruby on Rails), which the prototype was initially developed in. As part of the n-tier architecture, I developed an a object relational mapping layer to easily generate an object representation of the objects in the database, complete with their associations.
A demo of the CMS in action can be seen at Schools on the Net's demo site .