I have had this recurring dream for as long as I can remember.
I am in a deep circular pit. As I look up, I see a grey sky, and then a shadow comes over me and I move out of my body and out of the pit. I see that there is an ancient rusty mechanical piston above me, pounding me into ground, and I look around to see that the entire landscape is filled with copies of the piston, all pounding people into the dirt. The dream ends like that. There's no sound or color in this dream, and I invariably wake up from it with a feeling of hopelessness.