LONDON: A campaign for Art Series Hotels, the boutique Australian hotel owner, by Naked Communications Melbourne, has won the $10,000 2013 Warc Prize for Innovation with an idea that mixed PR, word of mouth and new product development.

Overstay Checkout addressed travellers' irritation with checkout times and allowed them to overstay in their rooms for free until those rooms were required by other guests.

An estimated 359% return on investment was generated on a modest budget of A$80,000. Room sales and spend on hotel services rose during seasonally quiet periods and the hotel owner was able to turn the offer on and off at will depending on its business requirements.

In a novel arrangement, the agency was paid a commission on room sales during the offer period.

The judges praised the simplicity, effectiveness and risk-taking nature of the innovation which attracted positive word of mouth far beyond the hotel group's home market.

Howard Draft, executive chairman of Draftfcb, the agency network, and chairman of the Prize judges, said the winner "showed us that, as well as flawless execution, you need to have a genuinely new and compelling business idea at the heart of your campaign to create truly effective innovation in communications."

Adam Ferrier, partner at Naked, thanked Warc "for providing such a public platform to recognise and encourage true innovation within the marketing communications industry", while Lach Hall, the digital strategist on the Art Series Hotel account and co- author of the winning paper, praised the client, saying "Art Series Hotels have been true partners in our quest to do innovative, category defining work".

"We all want to do great, innovative work, so when it happens it's wonderful to get it recognised," he added.

For the client, Will Deague, chief executive of Art Series Hotels, remarked on its strong relationship with the agency. "They too share our passion to innovate and smash category conventions," he said.

The Runner-up trophy was awarded to OREO's Daily Twist campaign, which marked the centenary of the cookie brand in the US by producing a new and topical creative expression online every 24 hours for 100 consecutive days.

Warc subscribers can read the shortlisted case studies in full here; non-subscribers can request a trial.

Warc is also running a quiz on the best of the Warc Prize entries, with a chance to win a subscription to Admap magazine.

In a further innovation, this year sees the first award of a Popular Vote trophy for the Longlisted entry that attains the highest combination of "likes" of its video on our free Warc Prize Vimeo page and downloads of its case study on warc.com.

This is currently being led by Human Coupons, a campaign for IKEA by Leo Burnett Canada. Voting will run until 00.01GMT on July 1, 2013.

Data sourced from Warc