As I've gotten more programming experience, interruptions have become less and less of a problem. As long as it's something that I've worked on in the last few days, I can hop in and get working pretty quickly. I don't know if my brain has just adapted to the environments I've been working in, or if I'm just a better programmer now. Maybe I've just become really good at ignoring people while seeming to be paying attention.

But taking a couple weeks off from a project really sets me back. It could take can entire day to get back up to speed.