Maybe Facebook's hackathon wasn't an all-nighter like founder Mark Zuckerberg prefers, but that didn't stop Facebook hotties Brandee Barker, Caitlin O'Farrell, Kathleen Loughlin and Raquel DiSabatino from enjoying themselves on stage with Thievery Corporation. Apparently, the crowd enjoyed them on stage too. "So awesome," commented Facebook's Dave Morin, despite being very taken by Google's Brittany Bohnet. Here's what we want to know about the video: Where's Sheryl Sandberg? What, mama don't dance no more? We hear her team insisted she wear jeans to the event, a fashion move the buttoned-up Sandberg almost never makes. But dancing must have been a step too far.