The Arcadiator is a CMOS based fuzz that has become a favourite within the DIY community. It's now also avaliable as a complete pedal.
It does octave down, octave up, pulse width modulation, alternating octaves modulation and more. From brutal octave fuzz to crazy retro game sounds.
For more info, check out the user manual
Stripboard layout for the Arcadiator 1.0