And some start the new year by making resolutions, for self-improvement.
In that spirit, what follows are resolutions that might - or might not - - be on the to-do lists of the denizens of the worlds of advertising, marketing and media.
John J Dooner Jr, Interpublic Group: I resolve to make sure all the calculators at McCann-Erickson are supplied with fresh batteries, even if they have to be bought from companies that aren't clients of IPG agencies.
Rupert Murdoch, News Corporation: I resolve to start another cable news network in the US that will be even more conservative than the Fox News Channel, just in case Strom Thurmond does get elected President.
Board of directors, Hollywood chapter, Screen Actors Guild: We resolve to organise protests against all the reality shows that the TV networks are hurrying to add to their primetime schedules, which are decimating our membership because the stars are real people rather than thespians.
Anna Nicole Smith, star of The Anna Nicole Smith reality show: I resolve to buy a dictionary and look up "thespians."
Sir Martin Sorrell, WPP Group: I resolve to petition the United Nations to ask if the world could skip from 2003 right to 2004, so we'd be at the start of the year when I've been predicting the advertising industry's recovery will begin.
Robert Shaye and Michael Lynne, the chief executives, New Line Cinema: We resolve to get in touch with that JRR Tolkien guy and see if he could write some additional Lord of the Rings trilogies.
Maurice Levy, Publicis Groupe: I resolve to undo some of the damage caused by the dismemberment of D'Arcy Masius Benton & Bowles by bestowing the D'Arcy name on the Publicis network, which could mollify the hurt feelings of longtime D'Arcy employees - those who still have jobs, anyway - while minimising confusion between the parent, Publicis, and its agencies.
Jim Cantalupo, the new chief executive of McDonald's: I resolve to visit our restaurants incognito to experience firsthand the problems - long lines, surly employees, bland food, boring menus - that are driving our customers away even as we slash the prices of our products and step up ads from DDB urging them to "smile".
Bonnie Fuller, the editor, Us Weekly: I resolve to finally finish writing the proposal I've been working on for that new magazine, Bonnie.
Martha Stewart: I resolve to finally finish writing the proposal I've been working on for that new book, Cooking Behind Bars: Parsley, Sage, Rosemary and Time Served.
John Wren, Omnicom Group: I resolve to continue to suppress the urge to produce and distribute charts depicting the inverse relationship between the recent financial performances of Omnicom and Dow Jones, parent of The Wall Street Journal.
Bill Ford, the chairman, Ford Motor: I resolve that as we spend this year celebrating the 100th anniversary of the company, we strive to improve our products and marketing to help make sure there's a 101st anniversary.
The cast of Friends: We resolve to start laying the groundwork right away for the dance-of-the-seven-veils, will-we-or-won't-we fandango that will culminate around a year from now with the startling, amazing news that we'll come back for an 11th season.