Albert V

My  last server was doomed, and its planned  replacement did not work out as planned. Something hat to be done quickly. What i just had around where parts for a planned cheap gaming machine: Mainboard, 4th gen Core i3, RAM, Case and PSU. Everything but the board came from a broken machine which I salvaged from the trash pile at work. The board was smoked, and i just had bought a new old one. A quick test showed that the system was using about 22W on idle. And that was that.
I ripped the HDD from the cubie as well as the SSD, HDD and Arduino-IO-Thing from the ditched Xbox86-project and shoved all of it into the new thing, prodded the already installed Devuan Linux until it did (mostly) what i wanted and called it a day.

Arduin-IO-Thing

As common desktop mainboards lack accessible GPIO's i use an Arduino nano clone over serial as a crude replacement. I need (or want) control of relays, RF transceiver, sensors and such stuff.

Console

Traditionally, my server also serves as a bedside media station. It saves energy (the server is running anyway, playing Video or not does not affect its consumption much) and is very convenient (again, the server is raunning anyway, so no booting).
I have a small display made out of a 15" notebook-panel and a LVDS-VGA adaptor from Ebay and one of those cheap, really tiny wireless keyboard-touchpad combos. The Display is powered from the server directly, and is switched by one of the relays.

Wifi

This is only the third Wifi Card i am using in one of my servers. Atheros AR5001X+ in 2006, Atheros AR9271 in 2013 and now Atheros QCA9882. Each one the result of some research to find a card with decent Linux support with open source drivers. Not easy, especially if one wants "newer" tech: in 2006 the troublemaker was 54Mbs, in 2013 150Mbs and in 2017 the "new" 5ghz band (well, and 540Mbs).
If you are in need of such a card, have a look at WikiDevi's page on  802.11ac devices. Neat.

Disposition

Most where repurposed as a normal desktop pc and given away.