If I genuinely thought the world was going to end soon, I'd immediately book a flight (assuming that I still can and the world hasn't descended into panic) to Yellowstone in the USA. I've always wanted to visit that place. I'd then spend the rest of what little time I had simply walking around, observing, and simply thinking over human history.
But the world's not gonna end anytime soon (at least, not in anyway that I can tell), so I'm just going to be playing video games over this holiday break.