The Happy Wackiness of

Visit the headquarters of in Las Vegas and you might find sales associates dressed as beer maids or Spiderman in the lunch room. And it’s not Halloween.

It’s just another day at an office that might just be the wackiest workplace in America. employees dress as web-slinging superheroes. (ABC News)

That wackiness is by design. Tony Hsieh, the chief executive of the billion-dollar online shoe and clothing retailer, believes that making employees happy means great things for his company.

PHOTOS: Tony Hsieh and other self-made superrich entrepreneurs.

“One of our core values is to create fun and a little weirdness,” Hsieh says. “We really recognize and celebrate each person’s individuality, and we want their true personality to shine in the workplace.”

Beyond silly costumes, quirks of the Zappos office include one section with a jungle motif and a room with couches and fish tanks where employees can nap. Perhaps even more impressive are employee perks such as free food from the company cafeteria, medical and dental benefits that are paid for 100 percent, and a life coach who is always on hand to help workers reach their goals.

Such benefits helped land Zappos on Fortune Magazine’s list of top 10 companies to work for.

But sometimes, even that’s not enough for a would-be Zappos employee. At the end of each new employee training session, Zappos offers new employees $4,000 to quit. Hsieh said that about two to three percent of trainees accept that offer each year.

“We don’t want employees that are there just for a paycheck,” Hsieh said.

Watch “20/20? Friday at 10 p.m. ET for the full story and check out a sneak peek below.