Course Website Framework
Over my years as a TA, I've developed a course website framework for posting announcements, homework assignments and solutions, lab procedures, etc. The main goal has been to minimize duplication of information and to easily integrate automatically generated LaTeX content (e.g. the homework problems and solutions).
For examples of some sites using this framework (or earlier versions), look here.
I've recently written a nice, detailed introduction, which explains the workflow for maintaining the website through the course of a course.