Free Distortion VST Plugin from Noizware:
TriDirt is a stereo 3-band distortion VST plugin. Features:
* Adjustable crossover frequencies with linked knobs.
* 7 different waveshapers for variety of sounds.
* Post filtering option (PF) applies low pass filtering at first and second band.
* Balance control applied before waveshaping for wide stereo effects.
* All bands and post filtering don’t use processing power when inactive.
Unfortunately the noizware site seems to have gone you can still download it from several places on the interweb.
Get it from here at KVR download