One of the most brilliant and enduring PR stunts of all time is the Nathan's hot dog eating contest.
I once had the opportunity to meet the quiet yet amazing PR guy behind the invention of this event, and I remain in awe.
This photo in USA Today is more brand promotion and positive goodwill than you could get for thousands of dollars of PR budget.
The trick for PR people is to uncover the hidden "hot dog eating contest" in their business or client. I firmly believe if left to their own creative devices (this rarely happens, BTW), truly good PR people can find a cool story in any company.