Apparently Facebook is a form of ID at the airport. Zach Klein, the co-founder of Vimeo and DIY.org claims that the TSA let him through security by identifying himself through Facebook when he realized he forgot his real ID.

Klein was already at the airport when he realized he didn't have a government issued ID on him. However apparently that wasn't a problem. The TSA told him he could use his Facebook account. He was so surprised by learning this that he shared it with his followers on Twitter, many of whom asked if he was joking.

"Got to the airport, realized I left my ID at home. TSA allowed me to use my Facebook profile instead," Klein wrote on Twitter on December 22.

He later wrote "Apparently this isn't remarkable; the TSA has a policy of using any "publicly available database" to verify identity. https://www.tsa.gov/traveler-information/acceptable-ids ..."

A shocked follower replied, saying "You're kidding. How is a profile you made and no one verified a valid form of ID? Really hope that's a joke."Klein swears that he wasn't lying and he may not have been.

This isn't a completely new policy for the TSA and they claim that they've been letting travelers use other means to prove their identity for a while.

A statement on the TSA website reads: "We understand passengers occasionally arrive at the airport without an ID, due to lost items or inadvertently leaving them at home. Not having an ID does not necessarily mean a passenger won't be allowed to fly. If passengers are willing to provide additional information, we have other means of substantiating someone's identity, like using publicly available databases."
There is no specific list of what these databases are, but according to Klein's story, Facebook is one of them.