I've often dreamed about finishing my PhD from a developing world paradise -- an Indian mountain top, or a tropical beach. However, there is always the fear that once I get there, I'll slack off. Since all of my leisure travel up until now has involved sitting in hammocks, reading books, and relaxing, this is a very reasonable fear.
I spent 8 days on an island last week, with no Internet, no phone, no one else but 3-4 staffmembers, most of whom spoke no English. There was electricity for 5 hours a day, in the evenings..
In that time, I managed to read 5 books, and write the better part of 4 research papers. Sure, they've been in my head for a while, but I was amazed at the rate at which I was able to put stuff down onto page (or in this case, into my laptop).
I go back to the beach tonight, and my hope is that I can finish all the papers off.
This sort of thing gives me confidence that I really can trust myself, and that if I wanted to jump on a plane at some point in the future for a few months, that it wouldn't destroy my productivity.