Mandelx

Mandelx is a very fast fractal generator that uses highly optimized assembly routines for calculations (multithreaded). Mandelx runs best on AMD processors. While the precision is enough MandelX uses the appropriate 32 bit SIMD floating point code path (SSE ,3Dnow!), then switches to 64 bit SSE2 and finally to FPU code. However you can switch between different code paths manually too. The FPU code uses 80 bit extended precision data so you can zoom deeper -without loss of speed- than with most other fractal generators. Integrated palette editor, Palette Animation, Record to AVI, and direct rendering to virtually unlimited picture sizes supported.

MandelX is portable and requires no installation.
Source code is included (Borland Delphi 5).

version 1.38
Subpixel calculation implemented for smoother images.
This works best with fine structures.