I get up around 7: exercise, shower and eat (in that order). Wake myself with OJ not caffeine (much more effective I find).
Work from 9am to 5pm in my day job - lunching at 2pm. Work from 6pm at home on personal projects / my personal company / consultancy. Till sometime between 8-11pm. Usually pause for 1/2 an hr for dinner at 9:30 if I am not already stopped working by then.
Religously in bed by 12pm if at home. If socialising (in, say, a pub) religiously home and in bed by 1pm (usually the next day is one I work 10hrs). Light Alcohol consumption only.
Weekends I work 8 hours (10am to 6pm) and keep incredibly strict to that timetable. Sundays I will sometimes work the mornings only.
last week I worked a total of 2 12hr days, 1 13hr day, 2 10hr days and 12 hrs at the weekend (69hrs). That is typical.
One thing I found was that it was about discipline and then developing some habits to help you concentrate.
I meditate for 10-20mins before I go to bed. I also make sure I read for around an hr before bed to wind down.
Cardio exercise first thing in the morning seems to keep me stimulated and awake for most of the day (I use wii sports and do some boxing). I also replace caffeine with OJ because that has a better effect for me.
But it is discipline that really does it: up at 7am every day with a simple but set routine for the first hour ensures you wake up really well. And being strict about bed time (and winding down before bed) ensures your fresh.
Good meals are another benefit. A good breakfast keeps me going till 2 (which is a good portion of the day gone!). A late lunch at 2 gives me energy for working at home and dinner at 9pm (the smallest meal) is just to boost energy levels slightly and to give me a simple break to the work.
I refuse point blank now to work longer hours at work: before I was working till 9pm and getting to bed straight from my PC at about 1am. But the thing is it's not a problem anymore - I am getting 50% more work done during the day right now than I did before so overtime isnt required :D
Be prepared to work hard though - it took me about 6 months to train myself into the basics and a further 18 to cement it. However this did involve finishing university and starting work (at the 6 month mark) meaning I had to reorder the routine setting me back quite a bit (I slumped for about 3 months as I mentioned before getting back on track)
EDIT: I should add about the 10hrs thing. I made this choice deliberately to limit myself to 13 hrs max but try my best to stop and do other stuff before I reached then. If I finish at 9pm for example there is loads of time to go hang out with a friend or just flake in front of the TV. I find this one of the biggest contributors to my heightened activity and concentration. Ive also taken to reading non-fiction like crazy in this time: stuff lik popular physics, sociology, body language, politics are my current fad :)
Also this clearly wont work if you have a partner - I am coming up with a routine to fit that situation though (as a relationship is on the horizon :)).