I have always liked to stay up late. I have best energy after 10:00 pm. Sometimes I stay up because I finally got a project started and stay up to finish. Now it could be procrastination that keeps me from starting "whatever" earlier in day or evening, but I do all kinds of things late. I do quilting , or bills, or computer work (my job involves lots of computer work, so often I get some of that done late. Glad DH doesn't mind, and late is a time when I can have "alone time".