Site Skins or Templates
I have added the ability to have multiple 'skins' for the web site. I was inspired by some of the DHTML sites including, CSS Zen Garden which allows people to develop there own CSS files and upload them on the site. Another site that is great for showing what can be done with DHTML is DHTML Central (which is the home of CoolMenus).
Check out some of the 'skins' that this site can have by going to the skin switch page.
These skins are achieved by defining styles using CSS. In addtion, the Top and Bottom code for the site is also maintained. The values are stored in a database and can be changed on the fly.
Site components are added to the template using a custom tagging system. This includes navigation, tittles, and copyright notices.
Some of the templates use the more traditional method of nested tables to achieve the desired layout. There are others which are pure CSS using <span> and <div> tags instead of tables.