Facebook has been on a spending spree, buying the messaging service WhatsApp for $19 billion and virtual reality firm Oculus for $2 billion this year. But CEO Zuckerberg has been more frugal with himself, cutting his salary to $1 in 2013, after earning nearly $2 million a year earlier.

Still, it's safe to say Zuckerberg, a billionaire, can afford the pay cut. The only compensation he did receive was about $650,000 to cover the costs for his air travel on a chartered jet.