Google Apps Sync for MS Outlook
Google Apps targets the biz users, but these users are so ingrained in using Microsoft Outlook that when they HAVE to use the Google web interfaces for email, calendar and contacts, the adoption is kind of "too slow".
With this took, Google has done just right to solve the user interface issue (and effectively reduced to zero the learning curve of the new Google Apps users). Perhaps, if the administrator is clever, the users of Google Apps would probably not even know their mail and calendar are supported in the back-end by Google Apps instead of the (expensive) Exchange Server.


