A perennial in the esoteric operating system space is ReactOS, a project with its roots in the 1990s which is doing a pretty good job of creating an open source clone of 32-bit Windows. They have a new version out, and it’s acquired some useful features.
Top of the list is a new graphical installer, removing the need for separate live and install ISOs, followed by improvements in video bug fixes and high definition audio drivers and subsystems. There’s a headless server install too, in which the GUI is suppressed. Perhaps most interesting, they are working on version syncing the open-source projects such as WINE on which they rely, meaning with luck that any improvements there will show up in ReactOS.
A while back we took a look at using ReactOS as a daily, and found it to be quirks aside, as usable as you’rd expect a Windows XP clone to be. Given that there are plenty of pieces of hardware and software around that still need an early-2000s era Windows to run, this remains an OS to keep an eye on.