My choice wasn't original but I still enjoyed doing it. I chose the Lethbridge Wind Guage.
The Images on the left are what I modelled my rendering after. I found them from various web sites. (I have never actually seen this wind guage) The Images on the right are obviously my pov-ray creations.
I tried my best to keep the proportions as accurate as humanly posible even though the images they are based on are all different scales.
If you look at my code in you would in fact see that the chain and ball are created at a diffent scale than the base. I then did a simple scale command to get the proportions to match.
What I found interesting in doing this is that the arches are not perfect circles. To get a curvature close to that of the real thing I simplty took a cylinder with radius of 1 and multiplied the x and y values according by the height and width respectively.
As I already mentioned, the base is cut from a cylinder. The chain links were done using two torus halves connected by two cylinders to get the stretched torus shape.
You may have noticed that the chain hangs at a considerable angle. This was quite easy to achive. The chain and ball are contructed together in a straight line up and down. A rotation of 23 degrees is then performed on the entire thing.
Lastly, I added a sky sphere straight from the tutorials. The only thing I changed was the color as it was red. You'll notice I didn't change all the colors as half the sky is blue and the other is purpleish. There is a noticable line where the color changes.
Here are the pictures!: