Justin Timberlake

He was a part of the buying group of MySpace

The famous singer turned actor who played the famous Sean Parker in The Social Network was in the limelight in 2011 when it was announced he was part of a group who bought the floundering MySpace from News Corp. for $35 million. He has also participated in early rounds of fund-raising for the photo-sharing service Stipple and Miso Media, a maker of music education software.

Lady Gaga

Google’s Eric Schmidt and Gaga invested in The Backplane

Famous for her meat dress, this celebrity whose twitter account is overflowing with more than 20 million followers is no stranger to social media. In 2011, she and Google chairman Eric Schmidt contributed to an initial $1 million investment in The Backplane, a community platform which worked on Gaga's social networking site Little Monsters.