For another controversial dictator, Fidel Castro, we assume he has economic control over a web of state-owned companies, including El Palacio de Convenciones, a convention center near Havana; Cimex, retail conglomerate; and Medicuba, which sells vaccines and other pharmaceuticals produced in Cuba. Former Cuban officials insist Castro, who travels exclusively in a fleet of black Mercedes, has skimmed profits from these outfits for years. To come up with a net worth figure, we use a discounted cash flow method to value these companies and then assume a portion of that profit stream goes to Castro. To be conservative, we dont try to estimate any past profits he may have pocketed, though we have heard rumors of large stashes in Swiss bank accounts. Castro, for the record disagrees, insisting his personal net worth is zero.
http://www.forbes.com/2006/05/04/rich-kings-dictators_cz_lk_0504royals.html