I need to provide a Web-based collaboration environment for a distributed group of customers who are working to produce documentation together. People from multiple organizations need to be able to access a shared Web site that allows them to share documents and hold online discussions regarding the content. Is there a low-effort, high-quality service out there that would save us from having to build this or host it ourselves?

Google Apps is worth a look. It takes very little time to sign up and create a site that you can restrict to invited members that meets your requirements to support users from multiple organizations who need to share documents and files. The Web interface is responsive and considerably more straightforward than many available content management systems. And it is software as service. You don’t have to build or host anything. You do need to consider whether the content being collaborated on is too sensitive for placement on systems you do not control and make your own decision about whether the document-sharing implementation provides enough version control for your project. Other free and low-cost hosted collaboration alternatives to review include OfficeZilla, HotOffice, TaskPark and WebEx WebOffice. Before you commit to a hosted collaboration solution, spend some time with it and experiment with the security settings to make sure that the system can and will enforce the access restrictions you want to implement.