One member of the Titan demogroup has coded an OpenGL 1k intro (1024 bytes) that draws a Mandelbrot set in 3D, or Mandelbuld (based on a GLSL ray tracer or something like this I guess).
You can download this intro here: 38644 by Titan.
Big pictures of this intro are available here: 38644: Mandelbulb 1k (3 pictures total)
Quick benchmark: 1280×1024, 20 seconds
- GeForce GTX 480: 508 frames, min FPS:19, max FPS: 31, avg FPS: 25.400
- Sapphire Radeon HD 6870: 508 frames, min FPS: 24, max FPS: 27, avg FPS: 25.400