Executives are 'monkeys'. Every manager is encouraged to spend 10-20 per cent of their time on goofing off with their team members.

Interviews often include unusual questions such as "How weird are you?" and "What's your theme song?" and feature the occasional shot of vodka.

Every new employee is offered $2,000 at the end of the training period – to quit. Customer calls can take up to five hours.

Weirdly enough, this isn't a madhouse. This is the wonderful world of Zappos. Although it's been around for 10 years, Zappos has recently become one of the US's most rapidly growing companies, on track to gross over $1 billion for the second year in a row.

The online retailer specialises in shoes (the name Zappos is derived from the Spanish word 'zapatos', meaning 'shoes'), but also sells clothing, handbags, watches, eyewear and jewellery, and shifts between 20,000 and 30,000 products a day.

All that in a recession. No wonder Amazon, America's largest online retailer, announced the acquisition of Zappos for around $880million in July.

Zappos company culture

A lot has been made of the unique company culture. Zappos even offers tours of its headquarters near Las Vegas and publishes an annual Culture Book full of thoughts from employees about what the culture means to them. There are uncensored company blogs, and everyone is encouraged to join Twitter and chat with customers.

Currently, 490 employees (out of around 1,500) have taken up the offer. "We like to embed the freedom to act as an agent to anyone," explains director of user experience and web strategy, Brian Kalma.

"There are really no rules around that. We mostly do it because Tony [Hsieh, CEO] and crew really trust the training. If you train everyone right, there's no reason why you shouldn't allow everyone to be an unedited, open agent of the company.

"There are challenges, and sometimes negative things are said, but the overwhelmingly positive response to allowing anyone to act as an agent on behalf of us is wonderful. It makes everyone feel like they're part of it as well. They have a say – a vested interest."

Success with Twitter

CEO Tony Hsieh himself has more than 1.4 million followers on the official Zappos Twitter account – not bad at all for an ecommerce store. "We try to think of ourselves not just as a company, at least on Twitter," Brian says.

"It's changing the way business is done. That resonates well to a lot of folks. We do happen to be a company, but we don't really talk about business; we're not necessarily being sales-y.

"We're just being real people and I think that transparency is attractive. It's really hard to say what the secret sauce is that gets people so interested, but I think that it's being real and authentic. Not many people are used to seeing companies be that way."

In fact, Zappos is all about customer service. New starters are asked to go through a four-week customer loyalty course, which includes two weeks on the phones with customers.

But most famously, Zappos offers a 365-day return policy and free shipping both ways (though sadly there are no plans to serve Europe yet). The customer base is loyal and three-quarters of sales come from repeat customers. There's a lot of positive word of mouth.