The Chroma.Camera Pin12 is the latest Chroma camera, a medium format pinhole camera with rise and fall. It does this by having three vertically-oriented pinholes. There are clips for each pinhole to mount a filter for the specific pinhole in use. The pinholes are 0.2 mm each with effective 25 mm focal length (about 15 mm equivalent) at f/125.
The camera is 6x12 natively, but has inserts stored within the body to set 6x9 or 6x6 format before loading the roll. It weighs about ten ounces and is roughly 1.75" D x 4" H x 7.25" W, so it should fit in a coat or hoodie pocket.
Photographer, Jed Pearson, took some dramatic photos with a prototype. Check out his results here.
Steve provides an introduction to the camera in this video: