1. Harry Kakavas: AlmostR$1 Billion. The biggest loss on this list goes to Harry Kakavas, an Australian real estate agent who made a fortune selling properties on the Gold Coast. Unfortunately for Kakavas, the more success he found as a real estate agent, the more he lost betting at the casinos.

Jim Mattress Mack  McIngvale is known for betting massive lumps of cash on his Texas sports teams, and the NFL playoffs are no exception. The 71-year-old retail furniture store owner betR$2 million on the Dallas Cowboys to beat the San Francisco 49ers in the divisional round on Sunday.