A few people at work want to use Outlook.  This is wisely refused by the guy handling IT, backed by management.  The email client of choice around here is Eudora.

The main thing they want is group scheduling.  What collaboration infrastructure is available to provide Outlook/Exchange "like" functionality?

General requirements:
- Group calendaring and other collaboration.
- Linux based server for the back end.
- Non-Outlook client on Windows for the users.  Migration to Linux for the users is not an option at this time.  :^(

I am aware of Bynari InsightServer and Samsung Contact.  Both of these appear to focus on using Outlook as the Windows client.  Do they have capability to use other clients?

What about Free solutions?  A really good web broswer based collaboration solution could be considered so don't leave them out of the mix.

I'll keep looking around on the web too.

Alan