Google Sites Service uses JotSpot's technology, it is a part of Google Apps and allows you to create web sites collaboratively.
Creating a team site as easy as editing a document. Use Google Sites to
centralize all types of information -- from videos to presentations --
and share your site with just a few people, your entire organization,
or the world.
Google offers templates, a rich-text editor, 10GB of storage for each Google Apps account and integration with other Google services.
Click an image to see example sites: