We use a redhat 7.3 (soon to be 9) server for our CRM package, Commonsense, running an IBM UniVerse backend. (The old versions are IBM support's fault). It also serves our document storage needs via Samba.
We also run several Suse10 desktops in our customer services dept.
Suse10 on our service dept Kiosk machine is used by workshop staff and engineers to read Manuals and partlists in PDF format, email and web search,etc, plus it serves PHPProjekt over apache for IT and delivery staff installation calendar planning.
Of our 20 or so users, only about 5 actually need the capability of MSOffice, and we have moved most of the others to OOo. (Actually there is only one who needs it really, but there are some apps we run with links to word etc, for file archiving, and one user has her own Macros).
Our Company Laptops all came with Windows preinstalled, so we left it there for the salesmen and their PDAs. Our Sertvice laptops dual boot windows and Suse10.
In general, our Suse desktops are no problem. Their users use them for email, web, the CRM package which runs in one or more terminal screens, word processing, spreadsheets etc.
We are installing an SBS 2003 server later this month, so we will probably start using the connector for Evolution.
Unfortunately, we have several (slowly being slimmed down though) packages that are windows server and workstation only, such as Sage, ACT!, Filestream, ESPOS,etc. We also run a Print/Copyshop which needs common apps like Photoshop, AutoCAD etc, for outside customers files, and has a Mac for the same reason.
But the main reason that we are still with Windows, is that most of our customers are, and we support the devices that we sell on our customer's networks.
Thus we need to use the software inhouse so that we can keep the expertise to support it in the field.
Ironically, the MFDs we sell all run NetBSD or Linux as their OS
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