travel journals: a question for my readers

The online travel magazine Matador runs this series where they publish pages from the readers' travel journals. I love it. And it got me wondering: do you guys use a notebook, scrapbook, journal while on the road? What do you use it for? Do you use it to write notes and doodle? Do you paste pictures and old subway tickets in them? do you do watercolor?
What format do you like? Does it have to be small to fit in your pocket? Does it have to be big to give you lots of writing space?
Do you like to have an extra pocket to store maps and loose post-its, or does that get out of control too fast?
What is the lifespan of your journal? How many continents and weird modes of transportation has it seen?




Let me know in the comments or by email: aelle_aelle[at]hotmail[dot]fr

Image credit: matador network.