The 7 Most Frugal Billionaires in the World

No. 4: Christy Walton (heir of the Wal-Mart fortune)

Net worth: $27.9 billion

Christy Walton is the widow of John Walton, son of Wal-Mart founder Sam Walton. Despite marrying into an impressively rich family, Christy wanted to raise her son in a normal and un-extravagant environment. After John passed away in a plane crash, Miss Walton donated their home, a 1986 estate outside of San Diego, to charity.