Like @mwester, I use a Raspberry Pi running the “OctoPi” OS image. OctoPi is an OS image that runs on a Raspberry Pi and has an OctoPrint server built in. OctoPrint is controlled via a web browser interface. A Raspberry Pi is a small single-board-computer about the size of a deck of playing cards.
Basically you send your prints to the OctoPrint service and it controls the printer. Once you send over a job you could shut down your computer if you wanted and the Raspberry Pi will take care of everything.
Setting it up is pretty easy:
Get a Raspberry Pi 4B 1GB (these things come in 1G, 2GB, and 4GB RAM sizes but 1GB is enough. I run on a Pi 3B+ (the previous generation of Pi) which are only available in 1GB RAM size. As I monitor how much RAM it is using, I still have more than half of the RAM unused. It’s very efficient. The Pi will cost about $35.
You’ll also need a 5v / 3a power supply ($8) and a microSD card. An 8GB card would technically be big enough but … I was at Micro-Center and discovered they don’t even bother to stock anything smaller than a 32GB card and even the top performing cards in that size were less than $15).
You would also need a case (Raspberry Pi doesn’t come with a case). The official Raspberry Pi case is $8. But most people who own 3D printers just print their own case … because you can make something that mounts to the printer.
Optionally you can add a camera. The official Raspberry Pi color camera is pretty good and it’s $25. OctoPrint also supports a pretty long list of USB web-cams. This lets you look at the printer to make sure it isn’t making pasta.
There are dozens of “how to set up OctoPi” videos on YouTube. It takes about 5 minutes to have everything working because it mostly self-configures the first time it boots (it creates a web server on the Raspberry Pi and when you connect to it with your browser, it walks you through a few tasks such creating your admin account and setting a password, etc.).
Once it’s set up, you’ll go into the OctoPrint settings panel (it has a wrench icon) and pick the “API” category. This is a key used to secure API access. There’s a really nice Cura integration to OctoPrint but it needs to know this key. So you copy the key, then on your PC/Mac in Cura, you’ll go into the Printer settings and find the option that says “Connect to OctoPrint”. You paste the key there.
IF your computer has Bonjour (all macs have it built-in. Windows traditionally did not have it built-in and you had to install Bonjour for Windows … or install iTunes for Windows and it includes Bonjour). I’ve “heard” that Windows 10 now has it but have not been able to confirm this. If you don’t have Bonjour you’ll need to find the IP address of the Raspberry Pi.
Bonjour is a zero-configuration protocol. You don’t need to know the name or IP address of the Raspberry Pi if you have Bonjour. Cura will broadcast that it’s looking for the service and the Pi will auto-respond to the request and self-configure (it really that easy). So really you only need to know the API key. If you have any Apple device (mac, iPhone, iPad, etc.) they all have Bonjour built-in. E.g. if you use the browser on your phone to visit “octopi.local” it will work as long as you are on the same network as your Raspberry Pi.
Once that is set up, you’ll notice that where you previously had a “Print” button in Cura, it is replaced with “Print with OctoPrint”. And when you go into the “Monitor” panel in Cura, you’ll notice you can actually SEE what the printer is doing (it shows you the video feed from the camera) and you can remotely control the printer. It’s really nice.
I use it because I usually have my iPad with me and I can look in on the printer from anywhere. I have a VPN into my home network so I can even check on my printer when I’m away.