WOK has released RING-O, a free ring modulation effect plugin for Windows.
Modulation source can be the left and right side of a stereo signal modulating each other, or a stereo signal modulated by RING-O’s internal oscillator.
The internal oscillator has different wave forms, the pitch can be adjusted manually or by incoming MIDI notes.
RING-O also features a diode ring modulator style setting for less clean sounds and the ability to adjust the modulation mix.
Ring-O is available to download as a freeware VST effect plugin for Windows PC.