With the much-anticipated fifth season of "Mad Men" off and running, the Internet is abuzz with fans analyzing Sunday's two-hour premiere and wondering where they can find that 'Zou Bisou Bisou' song to download. Hey, we don't blame you. It was pretty catchy.
To celebrate the return of Don Draper and company, we took a look back at the restless hiatus between seasons four and five, when clever New Yorkers turned stark white "Mad Men" subway posters into hilarious yet crude works of art. We rounded up 13 of our favorite ad enhancements found online below. Vote and tell us which ones you like best.