If you're going to market to people, you may as well make it fun.

Last year HBO splashed out on Boardwalk Empire's season premiere by sending period-era subway cars through Manhattan's train system. This year they were at it again, but this time using surface transportation: A team-up between HBO, their social partner BLT Communications, experiential agency Magnetic and car service Uber dropped a small fleet of 1920s Cadillacs, Rolls-Royces and Packards around Manhattan to offer free taxi rides.

The two-day event last week quickly had riders Tweeting and Instagramming the crap out of their vintage rides. And thankfully the vehicles weren't made over into garish billboards; a small, presumably magnetic panel with the show's logo was affixed to a door on either side, leaving the aesthetic beauty of the classic cars largely intact.

As friendly as the dressed-up drivers were paid to be, I'm going to cynically assume they refused fares to Brooklyn. Some things never change.Counting the subway stunt, this is the third time HBO's gone to the vintage vehicle well to promote the show. Earlier this year for the DVD release, they deployed a similar fleet to the streets of New York, Los Angeles and Chicago, where drivers in period costumes amusingly hawked the DVDs on the sidewalk out of wooden crates.

The network even transformed their retail store on 42nd Street into a speakeasy-style bar covered by a sliding wooden panel.

Visitors who slipped inside encountered a makeshift bar.

Ironically, however, the bartenders were not permitted to actually serve any booze. Prohibition made a brief comeback after all.