After the kids get to bed, I'm either burned out for the day or doing something else that must be done (laundry, etc.).
How do you make/find time to spend the time you want to in order to help with the family, run your part-time (or full-time) business into the evening (etc.), and still be able to have some downtime each day? How do you get focused?
In the evening, wind down the day, have a beer and plan out how you're going to use two hours in the morning tomorrow most effectively. Set one clear goal. Then...
1) Go to sleep
2) Wake up early (I recommend 6am)
3) Do the work you thought up last night
I find myself remarkably productive in this cycle. If you've planned well, you'll whiz through the tasks. Focus on "doing one thing" each day and you'll be racing through iteration cycles. I find that I'm usually so productive like this that I can comfortably keep the weekend purely for recreation guilt-free, rather than continuing to iterate on my down time and burning out.
This is how I built http://goodgecko.com
It's taken about 3 months* of doing exactly the above, now has paying customers and is an extremely satisfying "side project"!
UPDATE:
*I should elaborate - 3 months since the very barebones MVP. The MVP took about 2 months and featured basic surveys and a one-page sales site. The current product features web, mobile, popup and kiosk surveys and has a fully-realized sales site. The sales site itself took about a month to make...