Couple of years ago I had 30 hour layovers in Dec in MLI. There were two crews with this long layover per night. I will describe our layovers for you.
Arrive at 11ish pm. Go to hotel. Change. Ditch our respective psycho FAs. Go across the street to Steves Tap. Get obliterated. Try to find our hotel room. Pass out. Sleep till 1 or 2. Get up. Work out for about an hour. Go to the riverboat casino and cash in our free $5 coupon. Go to the buffet that is half price and use the fiver to pay the rest. I think the whole cost of the buffett was about 35 cents to us. Go back to room and try to sleep to get up at the as crack of dawn.

Have fun.