This video, via DivKid, takes a look at the Black Market Modular Colour Palette Eurorack module.

The Colour Palette is a unique module, in that it can host up to three Colour or ColourCV submodules. These are low cost, compact, DIY-friendly circuits that provide a wide range of functions including saturation, filtering, delay, and many others. 

The Colour Palette by itself consists of three high-quality VCA’s with serial and parallel routing options. It can be used as three VCA’s, even without installing any submodules.

Video Summary:

00:00 Features with cards installed
01:35 Tweet High Pass Filter
03:43 Woof Low Pass Filter
06:45 Features with no cards installed
09:05 Controlling multiple cards with one CV
11:47 Installing ColourCV cards
12:32 Assigning CV inputs
13:03 ColourADPTR
14:31 DIY Prototype Boards

For more info, see the Black Market Modular site.