Windows 95 running on Dosbox as a UWP on Xbox One.
As part of the Windows 10 Anniversary Update this summer, the Xbox One is being upgraded to support application development. In preparation for this change, Xbox One consoles enrolled in the preview program can be flipped into developer mode to allow development and experimentation to commence.
Whenever a system is newly opened up to developers, it's inevitable that it will soon be used to run either Windows 95 or Doom, and it appears that the Xbox One is no exception to this rule. The Dosbox emulator has been ported to the Universal Windows Platform, and that emulator has been used to boot and run Windows 95. Disappointingly, no Doom was attempted, but the shareware version of Duke Nukem 3D and the ZSNES emulator were both also demonstrated running.
The emulator is very slow, as it's using Dosbox's interpreted mode, wherein the processor is fully emulated in software. Dosbox has a faster dynamic mode that uses the host processor to execute as much code as possible, but the person who made the port, YouTube user vcfan, writes that this feature is currently suffering from some crashes in 64-bit mode. When enabled, vcfan says that the system "flies."