Certain tasks are more suited to the on-the-go environment than others. Plan ahead and set yourself work for your journey that will make the day ahead easier, giving yourself more time to focus on office-based jobs later. Before you leave the office, think ahead to the next day's meetings so you can use the journey home, or to work the next morning, productively to prepare.
Download applications to your iPhone, Blackberry, or iPad to help you make the most of your commute. Apps for the iPhone such as Oracle Business Indicators, and Sybase iAnywhere Mobile Office enable you to access company reports, your office desktop, check your website's performance, research venues, and perform a large number of other business functions.
A list of business applications available for the iPhone and iPad is available at: http://iphoneapplicationlist.com/apps/business/
Instead of listening to music, feed your brain with audio books, which can help you improve your professional skills, confidence, and knowledge. Even if you have a relatively short journey, listening for 40 minutes a day will accumulate 200 minutes worth of information in just one week. Audible.co.uk offers a subscription model with unlimited downloads of a huge number of audio books.
Alternatively, instead of using your commute to complete work related tasks, you could use the time to finish doing things you would otherwise do at home, for example, compiling a shopping list. This will allow you more time for relaxation later, as opposed to having a number of other chores waiting for you.
Always remember, the train isn't your office, so try to avoid making business calls. It's unprofessional and not only do you want to avoid becoming one of those irritating people who shout into their phone after losing signal in a tunnel, but you also don't want the whole carriage becoming aware of your financial plan for the next year.
Spending your commute working can buy you time during office hours, but don't push yourself too hard. Relaxing with a cup of coffee or even taking a power nap could be an equally smart use of your time if it invigorates you for the day ahead.