I am often amazed by a serendipitous shot like this. The tree is quite distinct, the lights have "strobed" at the mains frequency (50Hz so 100 flashes per second) and the line of the road is visible. You have a nice sinusoidal walking motion of 1/8 sec period which corresonds to the 12-13 flashes of the lights. 12 X 1/100 =0.12 sec which approx = 1/8 (0.125s) sec shutter period. Oh, and its a fun picture too! ~V~