It's now the second week of January, so I'm guessing that resolutions about going to the gym twice a day, only eating from your organic veg box and becoming evangelical about sobriety are long, long out the window. As Joey in Friends once said, "If you're going to do something wrong, do it right!" In which case, I can only suggest...
Handmade doughnuts from the Pippin Bakery (will be at the Henley on Thames farmers market on 22nd) or delectable cupcakes from the Hummingbird Bakery (a bit closer to home in South Ken' and Notting Hill).
Or slip off the wagon in style by joining the Wine Society. Top vino delivered straight to your door. The Mothership swears by it and so should you!
And finally, have a night of total debauchery and out and out decadence at the Wam Bam burlesque club in Soho - ideally located for staying on the sin-train long into the wee hours!