For software development, it is often necessary to have long stretches when you can do nothing but work. Sometimes those stretches only need to be a couple of hours, and sometimes they need to be a couple of weeks. When you need to focus on work, nothing can beat the holiday season when the office is empty or nearly empty and distractions are minimal (it's the same reason why I get so much done on the nights and weekends, too).
I usually try to use the holiday season as an opportunity to put myself on cruise control for a bit, wrap up "loose end" projects, and take a couple of days off to relax and see family. The last few years I have saved my days off and tried to have a massive block of time off at the end of the year. This year, I feel like I am going to use the holidays as a time to really focus and blast through some big projects, and take a couple of days off to see family.
Justin James is the Lead Architect for Conigent.