So I was on the way to the airport when i saw and took a picture of a cloud that looked like a cube/cuboid. http://imgur.com/a/MtWkO
I made 2 possible ideas from this
1. A shapeshifting cloud
It is basically a cloud that changes its shape every so often. The shape could be a regular cloud, 3D objects like the one in the image, text, and a few other things. To make it a bit more interesting, my plan was to have it occasionally display classified Foundation information.
2. A cloud castle
It would be a "special" cloud that you could actually step on. I also thought of making "cloud people" that act similarly to normal humans. I may make it so that you could only step on it after getting permission, otherwise you'd be considered trespassing. The culture may or may not be Medieval European, but this cloud was actually found in the Philippines, with just about no influence from the medieval European culture.
I am still confused as to how I should contain it, since as far as I know, you can't just move a cloud around. Also, the cloud was in a rather populated area with a bit of development going on. It may be fine to just "build around it", but I'm not too sure.
I'd like to know what you guys think, whether I should choose the Shapeshifter or the Castle. Ideas are also very welcome.