Posted on Electro-Music.com. Below is a picture and specs on the Dronebox2 VSTi. The Polycomb is similar but uses MIDI to trigger the comb filters. Looks interesting.
Click here for a sample of the Polycomb. There are also demo links to the software.

Description:
Dronebox is a VST effect that can turn your guitar into a sitar. It is a bank of six resonant, tunable comb filters with extensive modulation options. It can be used to create lush evolving drones or to add resonance to drums or whatever source material you wish to process.
Version 2 has a stunning new GUI, enhanced modulation and excitation possibilities plus a reverb effect. It also has a built in help section, manual and presets.
Features:
- 6 comb filters that can be tuned by note name, frequency, or by midi input.
- Volume, Pan, Polarity, Damping and Decay time controls for each comb filter
- An Oscilator to reinforce the drone.
- Advanced Excitation section to feed the comb filters with different noise
- Resonant filter
- Four LFOs and a Modulation Matrix
- Pitch bender to adjust the pitch of all combs at once.
- Delay effect
- Reverb effect
- Tool tips for each section.