Offtopic - Web 2.0 site(s) of the day

SlideShare is a service that lets you upload Powerpoint or OpenOffice presentations and have them be playable on the web, via a handy navigation toolbar. (If you're using unsupported presentation software, such as Keynote, simply export the file to PPT format before uploading to SlideShare.) This way, the presentations have a permanent URL for easy sharing; no more toting around a USB key drive and hoping it works at the client's office, for example.