I feel sorry for smallsteps, I know what it is like to have those persistent coughing fits where you just want to use a turkey baster and get what ever is clogging your throat out.
I think I like the 4th. Symmetry with out perfection. It catches my eye the little slight and subtle differences in the positioning of the parts.
That shot reminds me of an old factory filled with some kind of large pistons :)
One of the images it conjured in my mind was of the ancient movie METROPOLIS (Germany, 1927). hard to believe that is almost 100 years old, and still different things I see will remind me of it, and I have not even watched it since the early 70's. (I think I saw it on it's 50th anniversary in 77).
Metropolis was a great film! I haven't seen it since I was a teen I think - perhaps I should rewatch it with a different background.
I have been thinking of a re-watch since the inside of your piano shot, will likely watch it this evening to wind down Sunday.