The Pure Adapt double shift - how I max my productivity

Every young entrepreneur has the odds stacked against them: we all have less money, less experience, and less resources than a seasoned business veteran. We tend to make up for all of those things by working VERY hard. 99.9999% of the ideas that anyone has for a business are not unique or revolutionary in and of themselves, so success lies in the execution (and many ideas that are unique and revolutionary are horrible business ideas...just do a patent search on USPTO.gov sometime).

And like the rest of you, I am human. Averaging 12 hour work days over an extended period of time (I'm talking 6 months, not 6 years) may be necessary for success, but it's damn near impossible for me to sit in my home office for that long and be at peak productivity. My partners at Pure Adapt all are in the same boat - we all work hard and need ways to increase productivity without burning ourselves out. My biggest problem is that after 5 or 6 PM my productivity drops because I just worked a long day...but I WANT to work more and accomplish more, so I keep going at a reduced speed. At the end of the day I'm worn out, and I haven't actually seen another human being.

Our unique solution is something I call the "double shift". This is something we sort of stumbled upon, but are now making somewhat official for 2-3 days of the week. Here's how an "ideal" double shift day goes:

7 AM: Wake up, work out, eat breakfast, watch Sports Center
9 AM - 4:30 PM: Work from home, taking breaks every few hours for food. I need my time to myself to really get stuff done - I crank up the music and just rip through work
5 PM - 6 PM: Pure Adapt dinner. All (or most) of us get together and grab a beer and food, usually at a pretty nice place. The type of place that's a step up from a chain restaurant like Chilis but not too nice that you feel out of place drinking a beer and wearing jeans. We talk business and brainstorm ideas, but it's a relaxing a rejuvenating time.
6 PM - 10:30 PM: Work remotely as a team. Albany is a relative hotbed for the arts, so there are several great cafe's with free wi-fi (we use Wi-Fi Free Spot to scout locations). We usually grab a coffee (or tea in my case...not a coffee fan, and a wanna be tea connoisseur) and the caffeine serves well to counteract the beer and also wake me up a bit. I usually get a TON of work done on this "second shift" and it works real well for the projects we need to collaborate on.
11 PM - 11:59 PM: Read, watch TV, grab a snack, and go to bed

Now, I couldn't do this every day, but the reality is that this day is FAR more interesting/exciting/relaxing because I accomplish a lot and still get out in a social/business atmosphere. I also crave the motivation and encouragement of my peers - sometimes even though you know you're doing the right thing you need someone to look you in the eye and tell you to stay on track and stop questioning yourself.

So that's how I get shit done. What's your productivity secret?