In fact, you could build this produuct yourself in three months or so. But still, you have no per seat costs. The applications making up the suite fall under the category of Free Software. In the offline model, people send e-mail to a shared computer or computers within an enterprise and users connect to that machine to read their email. Some difficulty exists in attempting to determine the current extent of use of the offline model in the modern enterprise.
Opinions vary as to how much of the older offline models still exist.
One might think that the offline model has disappeared since so many of us retrieve and send mail over the Internet. Unfortunately, behind much of the mail we think of as Internet compliant, lies an offline, proprietary system limiting productivity. That off-line system does not encourage interoperability in the areas of messaging and collaboration many hold so dear. The offline model discourages interoperability and collaboration within organizations large and small. Guess what, they do use such systems and their decision-makers often don't even know it.