It's Benjamin Franklin and Congress' annual gift to South by Southwest: You lose an hour of sleep tonight.
At 2am, skip straight ahead to 3am and continue on with whatever movie-watching, party-going, bar-hopping, or panic-attack-having the night holds for you. And be sure to keep that time switch in mind as you plan out your screening schedule for tomorrow.
We know, we know; this notice becomes increasingly irrelevant as fewer and fewer people actually wear wristwatches or pocket watches or other such time-telling devices. Your iDevice or Android or whatever will (or should, at least) reset for you.