Once the preserve of rich oil exporters or nations with trade surpluses, like Norway, Kuwait and Singapore, an unlikely new breed of sovereign wealth fund is emerging – in countries with large deficits and deep debt. Sovereign wealth funds (SWFs), which first emerged in the 1950s, are traditionally associated with huge financial firepower. They control about $6.5 trillion, according to data provider Preqin, and have transformed the global investment landscape by snapping up stakes in multinational companies and landmark real estate in cities from London to Melbourne.