Lofibucket is a hobbyist site covering demoscene work, graphics tricks, and latency measurements, including Quake running on an oscilloscope.
HN links its oscilloscope Quake demo with delight, and cites its articles on desktop compositing latency and making a 64k intro.
Part of it would be done on a shader (mainly the visual portion, like the glowing and whatnot) but I think most of the effect would need to be done on the CPU.
You might be able to make it work with clever usage of geometry or tesselation shaders though, and maybe also transform feedback.
Honestly though, since the effect necessitates simple, low-poly geometry, doing the effect on the CPU shouldn't be too unreasonable, and would be where I would start.
EDIT: Actually, now that I look closer, the one on the right here[0] could be done more reasonably in a shader, I was thinking closer to the one on the left (and how it actually looks in the video).
[0]: hhttp://www.lofibucket.com/articles/img/speed_comparison.jpg
Lots of resource from the demoscene, especially 1K, 4K and 64K intros
- How a 64k intro is made [1]
- in4k site creation of demoscene 1kb, 4kb and 8kb intros [2]
- SizeCoding.org is a wiki dedicated to the art of creating very tiny programs [3]
[1] http://www.lofibucket.com/articles/64k_intro.html
[2] https://in4k.github.io/wiki/about
[3] http://www.sizecoding.org/wiki/Main_Page
And it does! Even when it's the only form of lag in existence, it's still noticeable -- see http://www.lofibucket.com/articles/dwm_latency.html for the notes of someone else who's noticed it.
I usually disable it on my work machine, too. I don't use flat themes anywhere, so I don't really need shadows, and I'm more than happy about the reduced latency.
Not to talk specifically about Windows 95, but older is better in regarding that until Windows 8 desktop composition could be turned off, which is a major source of latency [1]. I surely do miss that.
http://www.lofibucket.com/articles/dwm_latency.html
The classic theme is simple enough that it doesn't need GPU assistance (besides the usual 2D acceleration); and you get a noticeable decrease in latency from it:
http://www.lofibucket.com/articles/dwm_latency.html
That's it! The specific scene is at 1:14[0], and the article, is titled "How a 64k intro is made"[1].
<3 <3 <3
[0]: https://youtu.be/yei3mJm33SQ?t=1m14s
[1]: http://www.lofibucket.com/articles/64k_intro.html