Since the 90's Ireland is called the Celtic tiger in reason of the economic boom witch transformed the economy of Ireland.The country used to be and is still but maybe to a lesser degree in reason of the Economical crisis of 2008 witch affected badly the Irish economy.
For International People
Work in call centers
Many call-centers are located in Ireland and companies are regularly loocking for some new people, therefore, for a foreigner backpacking this is probably the easiest option if you have some of the skills requiered (IT knowledge, marketing knowledge, foreign languages fluency). It might be difficult to find a position in a call center without fluency in english but it's not impossible at all. There is yet many French, Italian and Spanish people in the country so there is not a huge demand for those languages but there is a constant need for smaller European languages such as Dutch or Finnish