Black Market Modular is kind of a new name to the eurorack scene. So far they only have one module out, but that is a really clever one, the Colour Palette. The Colour Palette is almost like a open source module. The module in itself consist of three CV controlable VCA´s, but the VCA´s also represents three separete channels to wich you can add a range of submodules.
Black Market themself have so far released the high pass filter Tweet and the low pass filter Woof that are available to buy bundled with the Colour Palette module. WMD have also contributed a few designs to the format that is available to buy separate. They are offering the Variac distortion module, the band pass filter Aperture and Wavecomplier, a eight stage wavefolder. Hopefully there will soon be more sub modules in this format available from other manufacturers as well.
If you think it sounds kind of confusing, take a look at this excellent walk thru from DivKid: