In this video, via John L Rice, George Mattson demonstrates the Division 6 Morpheum Eurorack module. 

The Morpheum is a VCA / morphing ring modulator. Here’s what Division 6 has to say about it:

Use it as a standard voltage-controlled amplifier. Run your audio into the Audio In, hook your envelope generator (mod wheel, pressure controller, whatever) to the Master CV In, and Morpheum does what any standard VCA does.

Want to test out your signal without having to have a CV present or let a little bleed through all the time? Turn up the Drone Level control to manually increase the gain of the amplifier.

The real fun comes when you add a modulation signal into the Mod Input. As you turn the Mod Amount knob, Morpheum transforms the modulation from none, through amplitude modulation and on to ring modulation. What makes this module truly unique is that the morphing (Mod Amount control) is voltage-controllable!

The Division 6 Morpheum is available for US $149. See the Division 6 site for details.