When building a web project, what sets of artifacts should be produced? How should they be organised so as to give a living DocumentationSet to the client?

Some discussion along this line in DocumentsFirstCodeLater. The idea seems to be evolving towards using a Wiki of some sort to capture design decisions and TheRoadNotTraveled so as to come up with a unified, overall view of the development life cycle.
----
Related:
* BugLifeCycle
* CommunityLifeCycle
* ExtremeLifeCycle
* IterativeLifeCycleProcess
* ProductLifeCycle
* SoftwareLifeCycle
* SystemsDevelopmentLifeCycle
* TechnologyAdoptionLifeCycle
----
CategoryDocumentation