HDPlex should make a small C14 to DC-in adaptor plate for SFF cases that don't have dedicated places to mount the DC-in, but have power extension cords that connect the PSU to a C14 plug mounted on the exterior, like the NCase M1, Node 202, etc.
Just a tiny plate with a hole in the middle would be very helpful for using a DC-ATX in certain cases. NCase is working on a new slim case which normally comes with a Flex ATX PSU, but would be able to accommodate the HDPlex 300W DC-ATX with a little velcro magic, but I'd have to drill a hole in it for the DC-In, which I'd really rather not do. An adapter plate to be installed in place of the C14 AC-in would be a much simpler and more elegant solution. I really think it would make a useful addition to the accessory catalog, please consider it Larry.