Garrett Rogers who covers all things Google for us here on the ZDNet blogging network has the skinny (and some screen shots) on some new file formats supported by Google's Google Base service:
Google has updated the uploader tool on Google Base, allowing users to associate more types of files with their items. Until today, uploading was restricted to images — but now users have the option to upload PDF's, Microsoft Word documents, PowerPoint presentations, Excel spreadsheets and more.
In a nutshell, once you upload a file to Google Base, not only can it be shared with other people that you need to share it with, it's searchable by others (in other words, it'll turn up in Google Search. You can also tag the file with additional metadata which in turn makes search more (or in some cases less) accurate.