My favs.
Goretex paclite.
A good daypack with expandable sides. Saves me using luggage.
Photocopied pages from a guidebook.
Other books/tapes from the library - to lean the language.
Small 50ml bottles from the $1 store for my soap and shampoo etc.
Plastic compass - yeah so you don't walk the wrong way even referring to the map.
Nokia phone - free offline GPS (doesn't need 3G Google Maps). Games and email. Music etc. Wifi for internet and Skype at the accom.
At home prior - Google Earth.