Before I left for 77 days in Europe, I read Henry David Thoreau's 'Walden and Other Writings' and 'The Art of Pilgrimage' by Phil Cousineau.
On my trip, I read 'The Beach,' by Alex Garland, 'Harry Potter & the Prisoner of Azkaban' and 'Harry Potter & the Goblet of Fire,' by J. K. Rowling, and 'Around the World in Eighty Days,' by Jules Verne - all highly recommended travel companions.
For more on my favorite travel books, check out this:
http://www.kahunna.net/books.shtml