I'm designing a pseudo-ducted quadrotor platform for industrial use. I'm still in the design phase as this needs lots of thought and careful planning. The concept is to keep everything as integrated and protected from the elements as possible. There is lots of space in the side cavities for specialized electronics which allows for the design of special purpose builds. The bottom cover shell also comes in different sizes in order to keep any added electronics (extra batteries for example) covered that may extend out of the bottom of the frame. It also features an integrated stabilized tilt camera.
The plan is to design three sizes, one for 12", 10" and 8" props. I've started with the 12" and will decide what is doable based on the resulting calculations. The body and frame design is just about complete. My first choice of material is carbon fiber but I still have to do some research on the lightest and strongest possible materials. I'm currently on weight calculations for an all CF version in an effort to calculate some data for motors, props and flight durations.
There is still very much to do on this. I'm hoping to feed off of the experience here on DIY Drones and maybe even find some collaboration on the way. I have lots of questions stored up for different stages but I'll stick to the presentation of the project for now ;-)
Here are more pics: http://diydrones.com/photo/albums/agrion-industrial-quadrotor-platform