My laptop is on all day, when I am at home, and I write most during the day. I used to be able to stay up late but that was before a job!
I don't really have an office or one spot; I try! I want to so I can have everything within arms reach but the sofa is comfy! If a kid comes in to watch tv or something I can easily move to another spot or even my room if I need privacy to write (which I do).
Do you have any routines or quirks when you write or create?