One of the interesting things I've read recently is about Microsoft's framework for Hosted Messaging and Collaboration.

It's a set of solutions for providing Microsoft Exchange, Sharepoint 2007, and other related technologies as a hosted service.

A hosted service provider model is different from the typical corporate in-house Exchange or Sharepoint environments.

In a in-house environment, you may have a few dedicated Exchange or Sharepoint servers providing messaging and collaboration services to internal clients, with the number of clients ranging anywhere from a few hundred to a few thousand (500-10,000).

10,000 clients may seem like a large number, but it really isn't - that kind of load can be serviced by a few servers of moderate capacity.

The HMC framework is intended for service providers hosting large scale deployments of 50,000 to 100,000 clients or more.

As service providers, each of their customers may have less than 10,000 mailboxes each, but combined they result in a very large scale deployment.

Having had prior experience with service-provider type hosted solutions, these types of large-scale solutions are very interesting to me.

Solution for Hosted Messaging and Collaboration v4.5