Folks on this subreddit still up at 3 am, what keeps you awake?

It's 2:58 am as I type this, and I see about 45 people online. There's even a term for it apparently - revenge bedtime procrastination. So, what keeps you awake? Did you not get time during the day to what you like? Or are you like me, worked out late at night and ended up with an adrenaline rush.