Talk about having some wealthy friends. Six people involved with Facebook made Forbes magazine's 2011 Billionaires List.
Facebook co-founder Mark Zuckerberg is at the top of the richest social networkers with an estimated $13.5 billion, according to Forbes. Zuckerberg had a good financial year, with his wealth jumping 238 percent.
And Zuckerberg isn't alone. Company cofounders Dustin Moskovitz, Eduardo Saverin and Sean Parker also made Forbes' billionaire list.
Moskovitz, the world's youngest billionaire, was Zuckerberg's Harvard roommate and Facebook's third employee. Today, he's worth $2.7 billion.
And Saverin, who started Facebook with Zuckerberg while they were in college, had a falling out with Zuckerberg - there was a lawsuit and countersuit involved. The parties settled and Saverin now is worth $1.6 billion.
As for Parker, the former Facebook president and co-founder of Napster also is worth $1.6 billion.
Rounding out Facebook's billionaires are Peter Thiel, co-founder of PayPal and a Facebook investor, is worth $1.5 billion, while Yuri Milner, who has invested in Facebook, Groupon and Zynga, is worth $1 billion, according to Forbes.
Mark Pincus, who founded social gaming company Zynga, is worth $1 billion while Eric Lefkofsky, co-founder of online discount provider Groupon, is reported to be worth $1.6 billion.