Five guerilla marketing campaigns

1. IKEA,  New York

From clear-walled 'rooms' suspended from cranes to a 30 foot parody of an Absolut Vodka ad with an apartments' worth of furniture glued to a billboard, Ikea has a history of great marketing stunts. During Design Week 2006, though, New Yorkers were treated to five days of comfort, Ikea style. The company teamed up with marketing agency Deutsch to make life that little bit more comfortable - with 650 different 'experiences' all over the city, including padded park benches in Union Square, bus shelters designed for 'comfort and flair', thousands of picnic blankets laid out in Central Park and even oven mitts on the number six train - all with a card bearing the slogan 'good design can make the everyday a little better'.

Sadly, the spirit of generosity didn't catch on: most of the furniture was stolen within days.

2. Half.com, Oregon

Back in 1999 when the internet was crowded with dot com start-ups, Half.com founder Joshua Kopelman quite literally put his business on the map by convincing Oregon town Halfway to become the world's first 'dot com city' by renaming itself Half.com for a year. In return, Kopelman offered the city a $100,000 package of benefits, including subsidised internet access, stock in the company, free giveaways and, crucially, a promise the change would boost local tourism.

The plan worked a treat: within weeks, Kopelman and residents of the town had appeared on various news shows, the Today Show, and the Wall Street Journal, and Kopelman's gamble had seen a very rapid return: just three weeks after the town renamed itself, eBay bought Half.com (the company, not the town), for more than $300m - a 3,000% return on the initial investment.

3. T-Mobile, London

In one of the most well-publicised guerilla ad moments of the last few years, T-Mobile transformed the concourse of Liverpool Street Station into an enormous disco, with hundreds of seemingly-innocuous commuters slowly joining in on an enormous dance routine, which was then aired during a high-profile advert break on Channel 4. The ad received a huge amount of press coverage, bringing T-Mobile's tagline, 'Life is for sharing', to the forefront of the public imagination. So much so, in fact, that the ad's success had unwanted consequences: a few days after it was aired, 12,000 teenagers descended on Liverpool Street in an effort to recreate the ad, forcing staff to close the station due to overcrowding.

4. Carlsberg, London

Carlsberg has been running the same 'best in the world' campaign for years now, but in April 2007, Londoners suddenly began to see its genius when the company left 5,000 £10 and £20 notes all over the city, bearing the sticker 'Carlsberg doesn't do litter, but if it did, it would probably be the best litter in the world'. Even though it was handing out cold, hard cash, the campaign cost Carlsberg just £50,000 - a snip if you compare it to the average cost of creating a television ad campaign.

5. Medecins du Monde, Paris

Drawing attention to the plight of people living on the streets is a difficult task in any city, but when French humanitarian organisation Medecins du Monde distributed 300 identical tents emblazoned with the charity's logo to homeless people in Paris, the sheer number of tents set up along the city's canals drew attention to just how many people were sleeping rough. The effect was immediate: Parisians voiced their outrage and the French government was forced to pledge €7m (£4.5m) to create 1,270 hostel beds in the city - making it one of the most effective guerilla marketing campaigns ever undertaken.