Updated 10/14/2013: Revised design, more positive positioning for camera platform.
This platform is designed to fit in one section of a Walthers N Scale 5 unit Thrall Double Stack container car, but should also fit other container well cars.
To use, just push the platform into place in the pivot (It should snap!) Then use rubber bands to secure the camera to that platform using the hooks on the corners. It's easier if you rotate the platform 90 degrees or so. There are detents built into the platform so you can pivot the camera and don't have to look straight down the track. Just watch your clearances!
I have a USB key recording camera that measures approximately 1 x 3 x .5 inches, and I designed this with that camera in mind, but it will also handle the 0.8" cube wireless cameras. The best way to run those is with the camera on this platform, and the 9v battery standing on edge in another well car behind it.