This was shot handheld at 1/5th of a second, so technically not a valid submission I suppose, but still a pretty slow handheld speed at almost 200mm and a fun example of what panning at very slow shutter speeds can produce, with the back of the car merging with the white lines in the runoff area.
The car is a Panoz Esperante GTR1 running on the Circuit Paul Ricard in south-eastern France. Shot on a Canon 1300D with a Sigma 100-400DG at 196mm, F29 (no ND at hand), 1/5th of a second and 100 ISO.