Most of them are just weekend projects, and took two or three days to create. Then I spend the odd few hours here and there. I also go to bed very late, which gives me ample time to work on stuff during the time when everyone else is asleep.
I wake up late, too, yes, but once in a while I'll be so engrossed in something that I'll get four hours of sleep. I'll generally have to make up for that sleep later that week, though.