i have a terrible time getting to sleep unless physically exhausted, leads to me being mentally tired quite often during the week. once asleep though, boy i can snooze for HOURS.
i'm also much more of a night person. i had a few months where i was unemployed, which pretty much lead me to developing what i would consider a more natural sleep pattern for me. consisted of going to bed around 11am usually, and waking up around 8pm or so, it was fantastic.