NEW YORK (CNN/Money) - Floyd Hayes, a British-born, New York-based adman auctioned off the rights to his voice on eBay last month for $750.

Hayes, 33, a creative director for Cunning Stunts Communications, a non-traditional marketing firm, pledged to spend this week screaming out the name of his sponsor every 15 minutes of his work day, no matter where he was or what he was doing at the time.

The winning bidder, Halls Fruit Breezers, was a natural tie-in: a throat-soothing product for someone who was planning to shout himself hoarse for a week.

Now that it's over, has Hayes gained any particular perspective from the experience?

Mostly, he says, that one week is "Quite long enough, thank you very much."

Hayes has shouted out the Halls name on the subway, in elevators, coffee shops – he must have frightened many wait-persons. He did his thing on the streets, in Madison Square Park, and Times Square.

"New York is one of the loudest cities in the world," he says. "In Times Square, a lot of people shouted back."

The promotion was right up the alley of Hayes's company, which the BBC credited with "The stunt of the century" back in 1999. That earlier event involved projecting the image of an 80-foot naked woman onto the Houses of Parliament in London to publicize FHM magazine's "100 Sexiest Women" issue.

Hayes says he came up with the idea of selling his voice as he surfed the Web, trying to come up with new ways to generate buzz. He saw that a pregnant woman had auctioned her belly for advertising space.

He wondered, "How far you could go and what else remained?" It came to him: "Why not sell your own voice?" He recalled that town criers were once common – although they didn't sell advertising – and decided shouting was the way to go.

The stunt followed in the footsteps of other over-the-top advertising campaigns.

Most Americans above age 40 can recall the television commercials in which a bell hop wanders through a hotel lobby yelling "Call for Philip Morris," at the top of his lungs.

Then there's the Aflac duck.

But one man, even if he does have the kind of plummy British accent so popular with Americans, trying to duplicate those efforts seems like a tough job. "It disrupts your day so much," says Hayes.

He says he would do it again, but not for $750. "It would have to be a little bit more," he whispered.

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