Updated Mar, 2nd 2013
Started by adjusting lens profile, distortion, and straightening. Set exposure down 1/3, Added two graduated filters (top/bottom) for darkening, and some vignette I played around with manual settings but afterwards ended up liking the "VSCO Film 02: N - Kodak Portra 160 VC -" present and adjusted manually from there (curves, saturation, shadows, clarity, and sharpness). I used the Spot Removal tool to remove some of the distracting white elements on the ground. My last step was using the Adjustment Brush to darken the garbage in the square hole and brighten the floor around the Octagon to try to create a sense of light filling the space near the opening.