Create rich, custom pages
Create web pages right inside your group
Use it for information about your group, shared documents, or anything
you want to publish online. Any member can view, contribute to, and
comment on the pages, from right within your group.

Build a knowledge base
Capture the content and information that may already be in your
discussions, in a way that's more easily accessible. Have a group for
discussing the best restaurants in your area? Why not create a page
that lists members' favorite restaurants?

http://groups-beta.google.com/intl/en/googlegroups/tour3/page3.html

Bill