Probably everyone knows this, but there are excellent fan-made Windows games engines for the most popular build engine games, with better mouse control, widescreen and high resolution support, and other modern enhancements.
https://lerppu.net/wannabethesis/ has 32 and 64 bit engines for Blood, Duke Nukem 3D, Duke Nukem 64 (yes, you can play the N64 version of Duke Nukem 3D, which has some interesting changes from the PC game), the Redneck Rampage games, and the DOS version of Exhumed/Powerslave.
BuildEngineGDX, from https://m210.duke4.net/index.php supports the following games:
- Duke Nukem 3D + World Tour Edition + official addons
- Blood + Cryptic Passage
- Shadow Warrior + addons
- Redneck Rampage + Route 66 + Rides Again
- Powerslave / Exhumed
- Witchaven 1 + 2
- TekWar
- Legend of the Seven Paladins
and Raze, from https://github.com/ZDoom/Raze/releases supports the following games:
- Duke Nukem: JFDuke, EDuke 2.0, World Tour extensions from DukeGDX and some minor fixes from EDuke32.
- Redneck Rampage: Nuke.YKT's reconstructed source available in the Rednukem Git repo.
- Blood: NBlood.
- Shadow Warrior: SWP and VoidSW.
- Exhumed/Powerslave: PCExhumed, with some enhancements inspired by PowerslaveGDX.
Today is a great time to be fan of Build engine games!
Edit: Doh! I forgot to mention the oldest and best known Duke Nukem 3D fan-made game engine, eDuke32, from https://dukeworld.duke4.net/eduke32/synthesis/
There might be even more fan-made game engines for these games now.