Apple
 System .85 / Finder 1.0
 The Mac 512K
 Image Gallery - MacOS
 What's New in Mac OS 8?
 The Mothership! - early Mac and Lisa archive
 Apple's Twiggy Disks
 Apple Lisa
 Apple Lisa 2/10
 Lisa Emulator Project
 Macintosh Stories: Busy Being Born
 Previous - a NeXT emulator (incomplete)
 Apple A/UX
 Archives NeXT
 NextStep 0.90 Screen shots
 Rhapsody DR1 Demo - YouTube
 Apple - Mac OS X
 Aqua Human Interface Guidelines
 Apple-History
 XGS/32
 Quark Catalyst
 Previous NeXT Emulator Home Page
 Previous Emulator Information Thread

Amiga
 Workbench Nostalgia
 Amiga Screen Shots (Danish site)
 HAAGE & PARTNER Computer [ AmigaOS 3.9 ]
 Official AmigaOS Portal
 AROS - The Amiga Research OS
 MorphOS Home Page
 Introduction to AmigaOS

Apollo
 Apollo Photo Gallery
 Apollo DomainOS info and archive
 Mike's Apollo DN3500 Page
 Apollo Domain Series 3500
 HP 9000/400t (HP-UX 9.x / DomainOS 10.4)

AtheOS
 AtheOS - free alternate operating system
 Introduction & Review of AtheOS 0.3.7 - OSNews.com

BeOS
 First Look at YellowTABs Zeta
 BeOS 5 User's Guide : Table of Contents
 Haiku Operating System

Tandy Deskmate
 Tandy's deskmate (GUI)
 Tandy 1000 TL/2
 TVDog Tandy Archive
 Tandy Sensation Demo - WinMate - YouTube

GEM
 Screenshots of GEM
 GEM Workshop
 GEM-related news and development
 Gem Programs
 NeoDesk - A revolutionary replacement for the built-in desktop
 ATARI.ORG / Pathfinder : ST : Emulation
 The Little Green Desktop - The Real Atari ST!

GEOS
 Geos Web Page
 GEOS Download
 Sean Huxter - Commodore 64 Work
 Remember Q-Link
 History of GEOS for Commodore Computers
 PC/GEOS History
 Unofficial GEOS Web Page

Linux / Unix
 KDE - Screenshots
 GNOME
 Enlightenment Home Page
 Official AfterStep Site: Themes Page
 icewm - Home Page
 The MGR Window System
 Getting Started with Motif
 More Window Managers for X
 WineHQ
 Unix Desktop Environment-Project
 DECwindows User's Guide
 IRIX Interactive User Interface Guidelines (PDF)
 Solaris 10 Build 69
 The Machine Emulator
 Peter's Sun3 Zoo
 Sun3 Archive
 The NetBSD Project

OS/2
 OS/2 V1.0 (non graphical) screen shots
 OS/2 V1.1 and 1.2 screen shots
 OS/2 V1.3 screen shots
 OS/2 Warp, PowerPC Edition
 OS/2 Warp 4 Desktop Tour
 eComStation Screenshot Gallery
 Project Odin
 OS/2 Warp History

Perq
 PERQemu: A PERQ 1 emulator
 PERQ Workstations
 FAQ for PERQ Graphics Workstations
 DigiBarn: PERQ T2, Ad and other PERQs
 Perq Single User Systems Overview
 Brochures for Apple II and Perq (1979)
 Perq Floppy Disk Images
 Perq Documentation
 Video of a PERQ on Youtube

QNX
 QNX Photon microGUI
 Get QNX Realtime Platform
 QNX DEMO disk

RISC OS
 RISCOSltd
 IYONIX pc
 History of Acorn & RISC OS
 Acorn RISC OS
 Technical history of Acorn
 RISC OS, !Draw, menu, and file save test - YouTube

Visi On
 Visi On History
 Computer Chronicles - Video of Visi On and Apple Lisa
 VisiCorp speaks.
 VisiCorp 1978-1984 (PDF)

Windows
 ReactOS - The future replacement for Microsoft Windows
 98lite: Windows98 *without* IE
 The BOB Chronicles
 Microsoft® Bob™ version 1.0 for Windows®
 TechTV | Remembering Microsoft Bob (Video)
 Innovative Systems I have Used - HP New Wave
 Packard Bell Navigator
 Calmira home page
 Die Windows History (german)
 The Windows® 95 User Interface: A Case Study in Usability Engineering
 Microsoft Does Windows - InfoWorld, Nov 1983
 Fall Comdex 1983 Part 3 of 3
 Windows NT, December 1991
 Microsoft Windows 3 and NT, 1991
 Bill Gates demonstrating NT in 1991 (part 4 of above)
 The Secret Origin of Windows
 Usability Expert: Windows 8 on PCs is Confusing, a Cognitive Burden
 Design guru Nielsen: Windows 8 UI 'smothers usability'
 Get Great Windows 8 Features Without the Upgrade
 Windows 1: VGA Resolution

Xerox
 Xerox Alto Operating System And Alto Applications
 The Xerox Alto Computer
 DigiBarn: A Brief Telling of the story of the Elixir Products
 A Decade of Research @ Xerox PARC
 Xerox Alto computer
 SmallStar (Bitmapped screen shot of Xerox Star)
 Xerox Star Historical Documents
 Xerox Star Research
 Designing the Star User Interface
 The Xerox Mouse
 Xerox Mesa System Emulator
 Xerox Star Professional Workstation (1981) - YouTube
 Xerox Star User Interface (1982) 1 of 2 - YouTube
 Xerox Lisp - Data Analysis Networks in DINDE (1986) -- Part 1 - YouTube
 The Smalltalk-80 Programming System - YouTube

Future GUIs and previews
 ROOMS 3D
 3DNA
 Croquet Project
 Doom as an Interface for Process Management

Misc
 Doug Engelbart 1968 Demo
 Blit Terminal
 PCmuseum - screenshots of misc old OSes
 MenuetOS.org
 Symphony OS
 SkyOS -- Screenshots
 Plan 9 and its window manager "8 1/2"
 The Microwindows Project
 BTRON-based Products
 Tilcon Software Limited - Graphics Editor
 ETH Oberon System / Gadgets Desktop
 Pascal Graphical Environment
 SymbOS
 History of the graphical user interface
 Tektronix 4404 Smalltalk Demo (1984) - YouTube
 The HP150 Touch Screen: a cautionary tale at Commonsense Design
 Hewlett Packard Touchscreen 150 Computer - YouTube
 The H.P. Touch Computer (1983) - YouTube
 Using Magic Cap

General UI
 Bad Designs
 The condescending UI

Videos
  Toastytech Youtube Videos (screw youtube and their autoplaying "recomendations")

Downloads

Downloadable GUI programs.
TechKnight.Com | Endangered Software Archive Windows 1.01, 1.03, 2.03 and MS-DOS 1.10.
VisiCorp Visi On Bootable 1.4 meg disk image - includes the tutorial and the word processor (this requires a Mouse Systems PC Mouse compatible serial mouse to run)
A preconfigured Visi On zip file of Visi On with executables for XT and AT computers. This includes Graph, however Graph will only run on an XT. The Original unaltered files from the install disks, and Floppy Disk Images dumped by various utilities.
Visi On hard drive image for use with MESS, mess1001_w95.zip needed to run it, and the required MESS ROMS: IBMPC.ZIP, PC.ZIP, and IBM5150.ZIP
Visi On Manuals:

Visi On AM Setup Guide.pdf Visi On AM Users Guide.pdf Visi On Calc QuickStart.pdf

Visi On Calc Users Guide.pdf Visi On Calc Working In Windows.pdf Visi On Graph QuickStart.pdf

Visi On Graph Users Guide.pdf Visi On Word QuickStart.pdf Visi On Word Users Guide.pdf

Windows 1.01 1.4mb boot disk - A self contained pre-configured easy to make disk that boots to Windows 1.01 on any PC.  Take the Win 1.01 challenge!
(1.x Apps: WineMine, Balance Of Power, PageMaker 1, VGA/VESA Driver, Demo Apps, Cake!, More Sample Apps)
(2.x Apps: Corel draw 1.10d, PageMaker 3, PC Mag Permance Tests, Designer 2, Klotz, PubTech File Oranizer 2.11, Paradise & Video 7 Drivers, Kermit, AMI Pro 1.2 [Spanish], ABC Flowcharter 1.11, PC Paintbrush Win1.22, Draw Plus 1.1, Magic Screen Saver 1.02, Metz Desktop Navigator 2.41,
2.50, 2.53, Comand Post 5.2)
Windows 95 Manual.pdf - manual for Windows 95
GEM World Download GEM 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2.0, 2.1, 2.2, 3.0, 3.01d, Viewmax, and GEM source code!
BeOS V5.0 Personal Edition - a FREE version of BeOS 5 that can be installed from Windows.
QNX Demo Floppy, Modem Version V4 - QNX OS + Photon GUI + PPP  + Voyager browser on a single 1.44 meg disk!!!
QNX Demo Floppy, Network Version V4 - QNX OS + Photon GUI + LAN  + Voyager browser on a single 1.44 meg disk!!!
QNX "Floppy" Demo CD ISOs - The same floppy disks demos, but as bootable CDs
QNX Extensions - a complete list of extensions for the QNX 1.44mb floppy demo.
QNX 6.21 Install/Live CD
Get QNX Realtime Platform - Evaluations versions of QNX.
Download Oracle Solaris - Solaris  .ISOs
Basilisk II - A free Macintosh emulator (emulates color 68K Macintoshes). You will need one of the Mac Quadra or 1024k ROMs
vMac - A free Macintosh emulator (emulates a MacPlus). You will also need a Macintosh 128k ROM also old versions of MacOS
MacOS 7.5.3 and the update to MacOS 7.5.5 - Straight from Apple's web site. And because I get asked so much:  Installing Mac OS 7.5.3 on Basilisk II and  CFM-68K Runtime Enabler 4.0 for Netscape and Archived versions of Netscape for 68k Mac Also Appearance manager to give MacOS 7.5.5 the MacOS 8 3-d look.
Apple IIGS/OS 6.0.1 - Straight from Apple's web site
The Apple II Desktop - a Macintosh like desktop for the Apple II series (Now includes floppy disk images).
ApplePC 2.52b emulator - an Apple II emulator that can run the Apple II desktop. Also needs the roms.
Breadbox Ensemble Lite
Geos for the Apple II
GEOS for the C64 and C128
The eComStation Demo CD - A free demo CD of the latest and greatest version of OS/2
OS22Demo.zip - An animated slideshow demo of OS2 Version 2.0
OS2demo.zip - An animated slideshow demo of OS2 Warp V3
Acorn Archimedes Emulators  - Emulates RISC OS 2.0 - 3.11
DESQview and DESQview/X
OS/2 Workplace Shell for MS-Windows 3.1 (does not work on Windows 9x)
Prodemo.zip - An animated slide show of GeoWorks Pro (PC-GEOS) Version 1.2
NewShell for Windows NT 3.51 - add the Windows 95 shell to NT 3.51
NewShell 2 for Windows NT 3.51 - same as first version except fixes a couple of compatibility issues.
PubTech File Organizer 2.11 for Windows 2.x
PubTech File Organizer 3.10 for Windows 3.0
Calmira Desktop for Windows 3.1
Screen Savers for Windows 3.1
Allgemeine Downloads (has MS-bob)
GlobalView 2.1 for Windows 3.1, 95, 98
SunOS 4.1.4/Solaris 1.1.2 CD-ROM ISO for Sparc Sun-4 machines.
GlobalView for X 1.05 - SunOS 4.1.4 version
GlobalView for X 1.00 - SunOS 4.1.3 version
Power Menu 4.11 (A text based Menu/File manager for DOS)
Tandy Presents the World of Multimedia (made with the sounds from Windows 3.0 MME)
Video 7 VGA1024i and Paradise driver disks - 256 color hi-res Windows 2.x drivers (and others) for these video cards.
NewWave Desktop - HP NewWave Desktop for Windows 3.0
Central Point Desktop - Central Point Desktop for Windows 3.1
Tandy Sensation CDs - Includes Tandy WinMate
Xerox Rooms for Windows - Rooms for Windows 3.x
Mouse.zip - Microsoft's 1983 Bus Mouse drivers and utilities for DOS. Includes PIANO.EXE.
Salto.zip - The Xerox Alto Simulator for Windows with disk images.
Microsoft Word 1.15 for DOS.zip - Disk images of Microsoft Word 1.15 for DOS
MS Word 1.00 for DOS Manual.pdf - The original Word for DOS 1.00 Manual in PDF format.
MS Word 1.00 for DOS Manual 1.1x Update Pages.pdf - A set of pages to update the above 1.00 manual for 1.15.
Microsoft Word 1.00 PC World Demo.zip - A free demo of Word for DOS 1.00 distributed by PC World.
Previous NeXT Emulator .4 MMU branch for Win32 - The version I used, that I know works and runs on Win95.
IBM CUA Samples Diskette 1.0 - A sample program for DOS that demonstrates IBM CUA components.
AT&T Unix PC 3B1 Emulator.zip