The debt originated when Haiti declared independence from France which demanded reparations for loss of plantations and the slaves freed. Haiti borrowed from the USA to pay off France, and then had to pay the USA, which hence interfered with its elections to support those, such as the Duvaliers, who would protect its investment while siphoning off money for themselves. According to a letter in today's Guardian, the initial "debt" of 150,000,000 francs, subsequently reduced to 90,000,000 francs, was paid off in 1947, but the estimate of what had been paid to France, including interest was, in 2004, $21,685,135,571. No figure was given for what was paid to the USA. (And given one set of figures is in a sort of franc which may or may not be the most recent version, and the other in dollars, comparison is difficult.)

This is not normal debt, so artbrook's comments, normally valid, don't really count. Think how the USA would stand today if Britain had been able to apply the same pressures on its independence.