> Well I've got a mixed estate of 8 Pis
Quite a few here too. Main RPi3 runs off a 2TB disk, serves NFS, runs a USB weather station, email (postfix, dovecot) for three domains, Nextcloud with numerous apps against postgresql (fewer resource demands than MySQL) and various other thngs previously run by an x86 server. The big thing to get over was the deep seated uncertainty about the USB disk, but actually it's been trouble free.
Another one (Pi Zero) is plugged into the telly and runs OSMC, getting the data from the main server via NFS. Control is via Kore on various tablets, phones around the house.
Another (Model B) is fitted with a Hifiberry device and is plugged into the old and wonderful sounding hifi amp directly. This one mainly runs mpd, and a web based control interface, but also does some cron jobs for the network. Also run minidlna for local streaming to tablets etc.
And another is in a data centre Somewhere In Europe running as a fallback MX, a few lowish traffic web sites, a Nextcloud instance used to share data with friends, family and other collaborators.
Another one runs in the house of a friend, who needed a nextcloud instance to get him round a short term difficulty, but the Pi turned out to be so useful a much wider range of local services are now run.
The new Pi just ordered will replace the "main server". That leaves me with an original Pi, ordered in the first wave, a Pi ZeroW, and a spare Pi3 and a Model 2, all of which are used at one stage or another to play.
The most astonishing thing about the Pi to one who does not use them in their originally intended way, for education, is that they are as capable as they are. When one runs out of grunt or otherwise hits the inevitable limitations of the nature of the device and its price point, the creativity required to get things working well is a reminder of the most satisfying times in IT. When I find myself wishing for more RAM, or disk connections, or whatever, I remind myself that we in technology are probably too conditioned to expect bigger or faster, and that very often, being disappointed when an ideal is unattainable gets in the way of what is actually achievable. Or as Miranda says, "such fun."