4. Zach Galifinakis -- Absolut Zach Galifinakis really hit the mainstream in 2009 with The Hangover, but before he was a mega-star, he was a comedian who created a couple of shorts featuring Absolut vodka. The company allowed him to do anything he wanted, so he signed up Tim Heidecker and Eric Wareheim to assist, unveiling a trio of ridiculous -- and hilarious -- YouTube videos.3. Sean "Diddy" Combs -- Ciroc Ciroc spent a few years selling its vodka, which is made from grapes instead of grain, without the help of a star. But in 2007, Ciroc struck a deal with Diddy, whereby he'd get half the company if he would be responsible for endorsing and marketing it. Diddy agreed and immediately proved that celebrity endorsements work -- according to Ad Age, the company has grown 552 percent, bringing in many millions of dollars more in revenue, since Diddy came on in 2007.