Apropos of application season...
Graduate school is a long stretch of time -- 5 years (or more) for most people. There are few clear goals during that time, although the obvious one is to learn how to do good research, with the hope of getting a tenure-track faculty job. With this somewhat singular -- and difficult -- goal, it's easy to fall into the extreme of focusing only on your research to the exclusion of most everything else, or to waste a lot of time not really working. Both of these things may be OK for various individuals. (As some will undoubtedly respond, if you're doing great research, it can excuse a lack of many other skills. And many people don't mind spending an extra year at graduate school with a more relaxed lifestyle than life after graduate school.) But with the new year approaching, I thought it worthwhile to suggest some of the additional skills one should try to develop in graduate school over those stretches where you need to break from research -- skills which, unfortunately and understandably, are often given short shrift by the university. (Please add to the list in comments.)
1) Time management: How much are you working each day? (And how much time do you waste reading -- or worse yet, writing -- blogs?) Even if you don't set yourself to a regular 9-5 or 10-6 schedule, it's a good time to learn to manage your working and non-working patterns. My suspicion is that people who manage a regular work schedule graduate on average a semester or year earlier.
2) Writing/speaking: If ideas are our business, idea presentation is a big contributor to the bottom line. And if you want a faculty position, the ability to give a good talk to a general audience goes a long way. If your institution doesn't have a program for improving writing and speaking, start your own (like a student seminar series, no faculty invited).
3) Leadership: Find a way to lead a research project -- maybe advising/mentoring some undergraduates. Or organize a club or student group to make your department a better place to be. Eventually, the ability to organize people to follow your goals will make you more productive.
4) Entrepreneurship: Have you looked at the economy? And professor's salaries? Graduate school is where you're supposed to learn to be creative, and to develop specialized skills. It's quite reasonable to spend some of those creative efforts or utilize those specialized skills on money-making endeavors. While it's not for everyone, for some the tangible reward of money helps unleash creativity; for others, you may learn the satisfying lesson that your intellectual achievements bring you higher rewards than a big paycheck could (a lesson worth learning early on).
5) The skill to learn additional skills: If you're a theorist, learn to program a little. If you're a systems person, learn some probability or other theory. Maybe set aside a few days to learn time-saving Latex tricks, or some other piece of useful software. There are plenty of skills that will make you a better researcher/teacher/writer in the future.