Actors, politicians, your favorite rapper's favorite rapper—you name them, chances are they've stepped through the doors of Facebook's headquarters. Even after switching zip codes on more than one occasion, CEO Mark Zuckerberg continues to roll out the red carpet for celebrities and granting tours around his billion-dollar empire. Some have played a round of table tennis with employees, others have eaten lunch with execs in the cafeteria, while our nation's leader was given the green light to throw a town hall meeting. Needless to say, it's become the hotspot in Silicon Valley to visit. Here is a look at the high-profile guests who've made their way into Facebook headquarters.