Bertill is an insanely glitchy distortion unit based on models of circuit-bent hardware, as a free VST for Windows and Mac (Universal Binary). Actually, whether you should really believe that or not, I’m not certain: I’m only vaguely sure of the relationship of the massive digital mangling this plug-in causes and the obscure Handycam shots uploaded to YouTube of a circuit-bent setup. Regardless, the thing sounds wonderfully awful. The knobs are straightforward and will demolish your sound entirely if you like; dial different “types” for a variety of different settings. Some of the higher type numbers are actually fairly subtle. Good stuff.
Here’s what it can sound like hooked up to a pad from Sytrus:
Sure, theoretically you should use real circuit-bent hardware for this. But this is fun anyway.
The plug-in is the creation of a Swedish Betabugs Audio vet going by the name Shuriken, which is apparently a ninja star. (Nice domain!) Lots of other good things on the site. Here’s the circuit-bent setup, though you mostly see it rather than hear it. Use your imagination: