Oh I like this one. It sound really good. Harald based this design on the Moog ladder filter. It has mutliple outputs and feeding the 12db output into the second input it can even function as a sine vco. This filter is quite big in size but I tend to use it quite a lot.
https://www.haraldswerk.de/Filter/Ladder_24dB_Euro/Ladder_24dB_Euro.html
Difficulty to build: Hard