Scott Duncan, 29 - worth around $4 billion
Duncan (not shown) inherited the money from his father who founded the energy pipeline company Enterprise Products.
Dustin Moskovitz, 28 - worth more than $3.5 billion
Dustin Moskovitz, pictured left, worked on Facebook during its early stages and was Mark Zuckerberg?s roommate. He co-founded the collaborative software company Asana, a San Francisco startup, with Justin Rosenstein, at right.