Angry enough to punch a defenseless panda? Then come to New York.

Every week this winter, performance artist Nate Hill dons a panda suit, heads onto the streets, and challenges members of the public to take a swing.

"Hit me. Hit more hard," he urged passersby on a freezing afternoon at busy Union Square. "You know you're angry, you were angry this morning."

A towering figure in white panda paw gloves, bodysuit and a head the size of a prize-winning pumpkin, the panda hopped down the sidewalk like a boxer.

Hill, 33, said he thought up the persona of Punch Me Panda as a "community service".

"I knew people were angry. I knew people want to punch things, because I want to punch things," Hill explained.

He cruises busy thoroughfares, businesses expecting layoffs, and even goes on home visits, all as a one-panda relief valve in a world filled with angry people. "It will lighten their day," he said.

Many on Union Square rolled their eyes at the sight. Some confused Punch Me Panda with an advertising campaign. Others seemed horrified at the idea of punching anything. Or they might just not have been angry.

Then the idea started to catch. A woman gave a gentle jab. A young man fired a quick left-right. A group of men egged each other on, punching, kicking and shoulder charging the ever-patient victim.

Each time, the panda pugilists walked away, faces glowing.

"We both felt so good after," David Melman, a visiting 23-year-old farmer, enthused. "At the first punch I was kind of hesitant, but upon the first contact I could tell it enlivened the panda and I decided to go for it."

Tianna Robinson gave Punch Me Panda her best shot -- but she wasn't thinking of pandas as her knuckles landed.

"I'm dealing with relationship issues," Robinson said. "I envisioned the dude I'm dealing with and it felt damned good, it felt damned good."

Actress Chelsey Clime, 24, practiced her kick boxing skills on the uncomplaining beast. She looked radiant afterwards.

"It's great. Everybody needs to shake it out. You know, you can take a cue from dogs. Dogs, when they're going through something, it's cold or they're upset, they just shake it out," she said.

"If there's a panda to help us shake it out a little bit, I don't see any problem with that."

Without his panda suit, Hill turns out to be a soft-spoken man with round, horn-rimmed glasses. His day job is at a laboratory where he cares for fruit flies used in experiments.

He's a veteran of attempts to confront New Yorkers' deepest angst.

As Death Bear, he dressed in a menacing black teddy bear mask and went to people who had broken up with partners and wanted someone to carry away mementos of the lost love.

As Mr Dropout, he wrapped himself head to toe in white, something like the Invisible Man, and wandered New York embodying detachment.

"My purpose is to relieve some of the suffering on the street," he said, the panda head at his side, as he wound down from his latest performance. "I think a lot of artists are focused inward on their own predicament and I'm trying to be less of a selfish person."

His methodology skirts the line between making the panda a provocateur and a passive victim.

To attract a beating, he thumps his chest with a red boxing glove, which would-be punchers are invited to wear. "I'm not going to hit you back," he assures in a muffled voice.

But unlike the human chickens and other animal suits parading on sidewalks as part of business promotions, Punch Me Panda has a threatening side as he hops in and out of the crowd.

"I like to bring a little aggression to it," Hill said. "I'm trying to get people excited to punch me. Just to provoke them."

The blows leave him sore, but don't really hurt. He protects his chest with a black breastplate and cushion.

Some assailants take the moment seriously. One, a tall, nearly toothless man who'd clearly trained in boxing, unloaded a flurry of combinations until Punch Me Panda put his hands up in surrender.

"I just pretended I'd had enough," Hill explained later. "I wanted him to feel like he was doing something. That's part of the theatre."

Sometimes, though, the theatre gets a little too real.

"I got punched in the face twice today," Hill said. "When I took the head off, the first guy ran. The second one, I took the head off and he apologized profusely."

The seven or eight home visits he's made so far -- answering requests made on Twitter -- can be a little tense.

"I always get real nervous going to somebody's house that I don't know. But I have to remind myself that they must be just as nervous and they'd have to be real crazy to want to do anything to a stranger in a panda costume."

Hill says the project will continue for about another five months. Details of his work can be found on: http://natehillisnuts.com/