ScottsNewOS the small os with a GUI
Computers, Software, Operating Systems, x86 - ScottsNewOS. Runs on i386+ compatible, working GUI even on 4 MB.
https://scottsnewos.sourceforge.net/
RDOS operating system and the Neanderthal theory
Computers, Software, Operating Systems, x86 - RDOS. Multi-process/threaded protected mode OS for all i386+ systems, written in all 16-/32-bit Assembly in TASM, fully PROMable so can port to embedded systems with no keyboard and/or screen, stable and secure via segment protection and paging.
http://www.rdos.net/
The Mbius Operating System
Computers, Software, Operating Systems, x86 - The Mobius: SourceForge. A few screenshots, details, links.
https://mobius.sourceforge.net/
CuteMouse
Computers, Software, Operating Systems, x86 - CuteMouse. An open source mouse driver for DOS.
https://cutemouse.sourceforge.net/
DWin {TOASC}
Computers, Software, Operating Systems, x86 - DWin. An Open Source GUI and multitasking system for DOS.
https://dwin.sourceforge.net/
FreeDOS-32
Computers, Software, Operating Systems, x86 - FreeDOS 32. To extend abilities of FreeDOS into native 32-bit system, based on simple, fully expandable, modular core.
https://freedos-32.sourceforge.net/
FreeDOS Kernel Site
Computers, Software, Operating Systems, x86 - FreeDOS Kernel Site. Frequent updates with the latest FreeDOS kernel developments.
https://freedos.sourceforge.net/
FreeDOS
Computers, Software, Operating Systems, x86 - FreeDOS. Goal: complete, free, 100% MS-DOS compatible operating system with no enhancements or advanced features such as multitasking, protected mode operation, GUI.
https://freedos.org/