I generally stay up until about midnight; despite being a bit of a night owl I still find that I get tired quickly unless I grab some caffeine.
One hacker I know, however, doesn't fit this list at all; he has a ~24-36 hour day (the second derivative of the length of his day is limited to about an hour, however). This means he might be sleeping in the middle of the day for everyone else.
I have a 30-36 hour long day, and the only way I was able to rein it in and get to where I could sleep normally (I have a sucky non-programming related job that demands I be conscious from M-F 9-5) was to completely change my diet to a more hunter-gatherer style diet and start exercising after work.
On the plus side, i am now the strongest person at my workplace, which amuses me greatly. (Two guys will work together to pick up a 50" TV, I'll pick it up by myself just to freak them out, lol.)
One hacker I know, however, doesn't fit this list at all; he has a ~24-36 hour day (the second derivative of the length of his day is limited to about an hour, however). This means he might be sleeping in the middle of the day for everyone else.