Some good tips about productivity in academia from the Get a Life, PhD blog (h/t The Philosophy Smoker):
I tend to agree with the author and strive to have a similar work/life balance in my own schedule. I almost never need to do anything school-related after I have been at campus all day. My evenings are usually spent with Katie cooking, hanging out, relaxing, watching TV or movies, or goofing off on the internet. Part of it is just making sure I am really productive on campus. The other part is making sure I actually spend enough time on campus during the week so that I don’t have to bring my work home. But I’ve found that there is almost nothing I can’t accomplish so long as I break up a task into doable chunks that can be finished while I am on campus.