Capturing commuters' attention used to be a simple affair easily covered by out-of-home, radio and press. But then the digital age dawned, sophisticated mobile phones became essential kit and public transport filled with commuters retreating from the daily grind via their white headphones into the iPod world.
So it's not surprising that so many marketing developments targeting commuters focus on mobile. Embraced by traditional media as much as new, the platform allows advertisers to reach consumers almost anywhere and to keep their messages bang up to date.
Newspapers have expanded their offerings online and are now available on the mobile internet and as iPhone apps, while radio has also headed in the mobile direction, as a way of reaching larger audiences and providing additional content.
But there are still handicaps for advertisers hoping to reach the significant - and affluent - commuter audience. The lack of in-car DAB means the platform has not progressed as far as many in the industry would like, while other commentators point to the limitations that still exist in mobile technology.
But one universal truth remains. For the 25 million Britons who are bored by their commute each day, their journey to work is a time when they are willing to be distracted, opening up a wealth of opportunities for the imaginative advertiser.
1 Digital outdoor streaming
Digital outdoor is becoming an increasingly common sight for commuters, as moving images capture their attention on sites across the country. But now the technology has evolved even further, with the ability to stream live advertising messages on the screens.
CBS Outdoor used streaming technology for Nokia's campaign to launch its N97 handset in July, using the message "online as it happens". The campaign illustrated the handset's media-sharing functionality.
Live streams were fed to digital escalator panels and cross-track projections displayed Londoners' Facebook status updates, news feeds from Reuters and applications from Nokia's online platform Ovi.
Nicky Cheshire, director of CBS Outdoor's Alive division, says: "We concentrated the campaign in central London to reach 80% of all Tube users - about two million people. Similar campaigns would cost about £150,000 to £200,000 for two weeks."
The Nokia campaign was created by Wieden + Kennedy, planned and bought by MediaCom and produced by Grand Visual.
2 Newspaper iPhone apps
The iPhone and its cornucopia of applications has opened up a world of possibilities for engaging consumers on the move.
In July, the Financial Times extended its FT.com access model to include an iPhone app, signing Siemens as its launch advertiser.
Free to download, the app can be used on iPhones and iPod Touch models and allows users to access news, analysis and market data away from the office.
One option includes a world map showing changing stockmarket figures in different countries.
Results from the first month after launch show the app was the number one free newspaper app on the iPhone, achieving 72,000 downloads and 33,000 active users.
3 Motoring's wealth corridor
In April, JCDecaux added two superstructure towers to its inventory to target commuters driving into London on the A40 and the M3.
Together with its existing sites on the M4 and the A3, JCDecaux now covers all four "wealth corridors" into the capital. With the infrastructure in place, it has introduced a new package: The Wealth Corridor Network, which allows brands to advertise on all towers, with the potential to deliver 6.5 million impacts over two weeks.
The rate card for the four towers is £125,000 for a two-week campaign, as used by Dewynters to advertise the musical Oliver in July. JCDecaux has also conducted new research for advertisers wanting to reach commuters travelling by car, showing that the audience travels from as far as the South Coast and Warwick.
David McEvoy, marketing director, says: "Four million full and part-time workers live in the catchment area of the four towers. Over a two-week campaign, almost 600,000 commuters will see one of the towers, each viewing the ads an average of seven times."
4 Mobile radio apps
Mobile technology has allowed radio stations to extend their influence by reaching larger commuter audiences, not just those travelling by car.
For instance, NME Radio launched an iPhone app in August, which shot to number two in the UK iTunes paid-for music app chart. The app, which costs 59p, allows users to immediately purchase and download music played on the station.
Bauer Radio's London stations, Kiss 100 and Magic 105.4, extended their reach by linking up with The Independent's website in August to enable users to listen to the stations via an embedded widget on the newspaper's homepage.
The move follows the launch of Bauer's iPhone apps for Kiss and Magic earlier this year.
Bruce Mitchell, head of digital at Bauer Radio London, says: "It's an infant market, but once the numbers start coming in, advertisers will see the scale and reach. Online listeners represent up to 7% of Kiss's radio hours compared with all radio's average of 2.2%. The Kiss audience likes this space because we have a youth demographic."
Bluetooth technology has so far focused on the rail network, but Blismobile is now installing the technology on buses.
The service will initially be available on 50 buses in major cities across the UK and will complement the company's rail and Gatwick Express network, which has the scope to reach 25 million mobile devices.
Tim Jones, sales manager at Blismobile, says: "The platform is based on Bluetooth, but the call to action could be an SMS message. The applications are free to download and cost is based on the success of the campaign, so there is no wasted media budget."
At the end of September, the release of the final film starring the late Heath Ledger, The Imaginarium of Dr Parnassus, started a three-week promotion on Blismobile's London network, with calls to action aired on Titan's Transvision screens.
Blismobile charges advertisers 23p per successful consumer engagement - and the number of downloads is capped at 100,000.
6 Newspapers go mobile
Mobile technology allows newspapers to extend their relationship with readers and provide updates on major stories. Andrew Mullins, managing director of the London Evening Standard, says: "Mobile is the bridge between online and offline."
In May, the Standard launched its free mobile service. When readers text the number provided, they receive a link to the paper's website on their mobile browser.
And at the start of the month, the Standard shocked the industry by announcing its switch to free distribution. Mullins says: "There is a perception that the news is perishable after the last edition at 5pm - like supermarkets cutting the price of perishable goods near their sell-by date."
Meanwhile, CityAM wants to skip the download stage by putting its website directly on to mobile hardware. Lawson Muncaster, managing director, says: "We will have deals by the end of the year with Vodafone, BlackBerry and Nokia."
7 Event creatives
Turning a campaign into an event in its own right and generating headlines in other media is a creative way of encouraging people to buy a product.
Last September, The Times launched a "tease and reveal" outdoor campaign designed to get commuters to "think again" about the big issues of the day, using London Underground and Adrail sites at major commuter stations.
Phase one of the £3m campaign, created by CHI with Mindshare and Kinetic, used images with no branding. Richard Larcombe, head of brand marketing at News International, says: "The unbranded images generated huge interest, particularly online. Even our competitors ran stories questioning who the mystery brand might be."
The campaign, which also used press and TV ads, was the most successful for The Times in recent years. Larcombe adds: "We overtook the Telegraph on last December's six-monthly NRS figures, and we surpassed all key brand metrics."