When you wake up New Year's Day with a pounding head and a strong desire for greasy food, wondering where in the world you left your scarf/iPhone/purse/dignity, remember there's someone who had a worse night: the bartender(s) who had to deal with hundreds of people shouting for glasses of champagne at 11:57 p.m., baying for the umpteenth round of shots or ordering "two vodka-sodas, one Red Bull and vodka, two Miller Lites, no, two Yuenglings, and a Long Island iced tea." And they had to work on New Year's Eve. So Jan. 1 is a bar employee's Dec. 31, and the Black Cat is inviting everyone over for "The Post Amateur-Hour Happy Hour," billed as "an all-night happy hour for people who had to work last night." If you're a bartender, bar back or server, this is the time to have someone else pour you a drink. If you don't work in the industry, go apologize for ordering those Long Island iced teas. And buy your bartender a shot -- selected whiskeys are $5 all night.