I once upgraded H/W & S/W of a SCO UNIX system to a version that implemented TCP/IP, so we could connect it to a Windows box, thereby saving a key-employee's time when FAXing daily client service-usage reports. Before making the interconnection, large-forms had to be bursted, reduce-copied & copies manually fed through an unreliable FAX machine.
After the 2 systems were connected, much of that work process was eliminated, by slightly formatting & FAXing each client's report on the Windows box. The guy could then leave work 45 min's to 1.25 hour EARLIER each day... We think it precluded / delayed the loss of that key employee.
Of course, the sheer number of new, community-built/-maintained, FOSS Linux/FreeBSD/OpenBSD variants of UNIX-past make for lots of questions on their detailed usage, etc.