When I navigated to the hard drive icon in Tiger (the icon that sits on the dekstop) I found a strange folder I'd never seen there before and which I certainly didn't put there: bffffff8800. Inside were about ten more folders, with equally odd names like -01ffffffdaffffff-c1b1a1d3c1, all of them entirely empty. Do these look familiar to anyone? What could have possibly put them there? Anyway, I've deleted them.