Sometimes I find web sites that are so smart I wish I made them myself. Fiverr.com is one of those. On this web site, which actually have been online for about 2 years now, you can offer any [legal] job you want for 5 dollars (4 euro). Of this 5 dollars the web site will charge you 1 dollar to use their service. The jobs that are most common on the web site at the moment are creation of YouTube videos or songs, but there are also some really strange ones like to hire a Facebook girlfriend for a week.
So if you are artistic creating anything that doesn’t need shipping this is a really good way for you to earn money while traveling.