It has been a while since my last email on my adventures. I will give some catch up emails another time, meanwhile one question I have been asked is: How can you travel indefinitely (if you are not Bill Gates)? One way is to save money by visiting low cost countries, cooking your own food and using buses rather than planes. I have done this when I lived in Bolivia and had a good time on less than $500 per month.
Looking at the other side of the income-expense equation of traveling there are many ways to make income while you travel. I make more than I spend per day by running my business remotely via skype and email. I have met other travelers who can cover their travel costs indefinitely by travel writing, selling photos, teaching English, doing import-export of local handy crafts or working in local tourism businesses. Once I have paid off all my old business debts and credit cards I will be making more money than I spend. Yay!
Even if you don't make enough to completely cover all your expenses it can let you travel for longer than you could just on savings. Some of the travelers I have met work 8-16 hours per week to cover the week's expenses because they are paying expenses in a low cost country like Peru and earning money remotely in a high pay/high expense country like the US or Europe.
Another approach is the "4 hour work week" (Tim Ferris) one of working for a few months then taking a 3 month mini-retirement of traveling. Rinse and repeat indefinitely. His book and website also have lots of info on starting your own online business or negotiating to work remotely. I have met some Australian miners who earn enough in a year to travel for two years without working. I have also read of some miners in Australia who work 14 days straight and then take off 14 days living in Bali and traveling in SE Asia - again they do this indefinitely.
More ideas and travel tips at Travel Stack Exchange - a great place to ask and answer travel questions by the way! And other ideas on travel and money from Benny Lewis, the fluenent in any language in 3 months guy.
What are you long term travel tips?