PHOTOS: Rihanna, Blue-Ribbon Babe

Okay, so maybe it isn't exactly a ribbon on top of Rihanna's head as she headed out to dinner with friends in NYC last night.

But what is it?

Regardless, the singer was in a blue mood, at least in terms of her clothing as the mysterious kinda-hat on her head was complimented by her low-cut, thigh-high denim dress and a pair of electric blue heels.

Over the weekend, RiRi hit up a downtown Manhattan karaoke bar, where she sang tunes such as "Bust Your Windows," "Living on a Prayer" and "Before He Cheats."