In a corner of the office with a beautiful view, there's a graffiti-covered hot tub.
Alas, the hot tub is not filled with water. The landlord wouldn't let it happen.
In fact, before Facebook could bring the hot tub into its offices, it was forced to drill a hole in the bottom of the hot tub as a prophylactic measure to ensure it's never filled with water.
The hot tub was brought in ahead of one Facebook's hackathons. Hackathons are where Facebook's engineers build small new products that could eventually become something bigger. They're sort of like musicians just jamming.
The engineer who spearheaded the project, Philip Su, let us run photos he took documenting the installation of the hot tub.