NeoGAFs Kent Brockman
A modder has been working on a now-delayed ray tracing mod for the original Half-Life, but the same person does release a similar add-on for Quake.
User Sultim Tsyrendashiev, also known as sultim-t, has released their own mod for the original Quake, which implements full ray tracing capabilities. A trailer opens by saying, in the style of G-Man, that a similar Half-Life modification has had to be delayed, before the video then bursts into life by showing the new and improved version of Quake. A side-by-side comparison shows that, while still retaining the look of the original game, it's got lovely lighting effects galore, with some spectacular reflections, shadows, and overall illumination. It all looks very impressive, especially for a game this old.