While Chip's Challenge technically had its debut on the Atari Lynx in 1989, I think most people are familiar with it through its Windows 3.1 iteration, released as part of Microsoft Entertainment Pack 4. It's a fun little puzzle game - fill in blocks, find keys to open doors, avoid hazards, and make your way through over 140 levels of challenges (plus more fan-made level packs to add even more). It also famously had a sequel that went unreleased for over two decades owing to copyright concerns, finally launching on Steam in 2015. The original was also made a free download on its 30th anniversary in 2019, so puzzle fans owe it to themselves to give this one a try.