Update from future me: This is probably horrifically insecure, so run at your own risk. Although it's not too bad since it's only designed to run on a LAN.
The server for Itch, allows easy saving/loading and sharing projects with your LAN.
The Itch server is written in python.
Download python from https://www.python.org/downloads/ make sure you download python 3+
- (Linux only) Right click on the file and choose Properties > Permissions and tick "Allow executing this file as a program" (at the bottom)
- Double-click "RUNME For Mac And Linux.sh"
- Double-click "RUNME For Windows.py"
When you run the server it should say "Listening on http://<[your ip]>:8000" simply copy and paste the url that the server printed into your browser. You can also access the website from other computers, providing you're on the same network.
To stop the server simply just close the window, it might ask if you're sure but just press "Ok".
Enjoy! :D