I would love to hear about a non-exchange messaging solution, but you fail to name any applications client or server. Would you please name one? All I have seen is Evolution, which requires Exchange Server.
These products vary greatly in terms of comparable functionality and interoperability with other e-mail products, like Exchange and Outlook. In evaluating these products, the degree to which they provide similar functionality to Exchange should be examined closely.
On the desktop, alternatives include Ximian Evolution, Mozilla Mail and KDE Kmail. You can also find more applications at the Red Hat Solutions catalog and in online application catalogs such as .Knowledgestorm.
This was first published in May 2004