Moolah! The 3D Money Screen Saver for Mac

From Useless Creations:

You'll be drooling like an escaped mental patient as you sit and watch the endless money flowing across your screen in mind blowing real-time 3D graphics. Included currencies are US Dollars and Australian Dollars, but there are heaps of additional currencies from all around the world available for the full version, including Canadian dollars, UK pounds, and EUROs.