Some things you don't really fully realize until they are all put together in front of your face. Filling out some (exceedingly tedious) forms today, I had to write down all of the foreign countries that I have visited recently, and apparently, over the past five years I have gone abroad 27 times, to 14 different countries. The vast majority of that travel has been for scientific meetings of one sort or another, and mostly to various locations in Western Europe.
I know that I travel a good bit for science, and part of me looks at that number and says, eh, that's only about once every quarter. The other part of me, the part that remembers a quiet childhood growing up in Maine, almost never traveling more than a few hours drive from home, looks at those numbers in astonishment. It means that I have grown up to become one of those strange frequent fliers, for whom an airport is just a normal part of life, and I suppose that is how it will continue to be for as long as I am a practicing scientist.
I like this life, but sometimes it helps to remember how foreign it is to many others, and even my own younger self, who not only didn't know I would end up living such a life, but never even thought about the possibility.