I only have its descendant, the Benjolin, as a Eurorack module, but it does things with runglers (Hordijk’s own particular sort of FM / feedback CMOS shift register chaos generator) that nothing else can quite achieve, as long as you’re not necessarily looking for melody or tonality.
One semi-modular that’s now probably passing into legend and perhaps obscurity is the MFB Kraftzwerg II, which I have an example of, that has triple oscillators, a shedload of patching options and can sound huge.