As inflationary pressures mount anew and the financial markets increasingly shun U.S. Treasuries, an inflationary depression can evolve quickly into a hyperinflationary great depression. Although hyperinflation became inevitable in the last decade, the onset of the process just recently was triggered by Fed and the Treasury actions in addressing the systemic solvency crisis. The process would be accelerated by unfettered and unfunded government spending that appears to loom in early 2009.
This is from John William's excellent web site, Shadow Government Statistics. Unfortunately you need a fairly pricey subscription to get to the rest of the article quoted above. I can't blame Williams for that, ya gotta make a living. But there's a lot of other great stuff there available for free, including special reports on hyperinflation and the money supply. This is highly recommended material.