An "S" Hook got embedded in the tire midway between the center line and the sidewall.
The hook spun around with the tire, with the exposed end of the hook scraping against the outside of the fender (making quite an awful noise).
Aside from scraping the paint, the hook actually indented the fender, making the area below the pinstriping concave instead of the slightly normal convex form.
Click on the small images for larger photos