OpenTTD 1.11
Oh man, this is still my favorite game 27 years later.Chris Sawyer (the original developer) is one of those OG 10x developer. Built an entire game + AI + windowed GUI in Assembly in 1992! Even before Windows 3.11 came out.I still remembered my first impression back in 1994 distinctly.
I can open 20 different windows in Transport Tycoon and each window follows its own respective vehicle like a drone cam.The GUI windows themselves can be resized smoothly and piled on top of each other. Something that older version of Windows couldn't do.Also, the game was fairly small in size and incredibly stable.I thought to myself, this developer was a mega genius!