Loads of celebs have signed up to promote a drink - but it's not something fizzy or unusual, it's MILK! Here's Harry Potter star Rupert Grint with a milk moustache.
His character Ron Weasley would be more likely to be glugging some butterbear down but Rupert says he's loves milk. A make-up artist makes sure his moustache looks just perfect.
Here's the finished poster. "I come from a big family and my mum always made sure we had lots of milk to drink as kids," Rupert said.
Star Usher is also part of the campaign to get people drinking milk. Wonder if the American R&B superstar likes milkshakes?
Here's four members of The Wanted - and guess what they wanted? Yes, you've got it, milk! Maybe this milk-moustache thing will become fashionable? They certainly look cool.
Actor Ryan Reynolds plays comic character Green Lantern in the film and it seems he is also a fan of the white stuff. Cow's about that?