Online Document Sharing

• Google Docs and Spreadsheets
• Zoho Writer
• WriteWith
• YourDraft
• Scribd -- upload and publish documents online
• Buzzword -- collaborative authoring for documents online
• Thinkature -- through a workspace you can share ideas, content, drawings, and chat with students and colleagues

Personally, the two I've tried are Google Docs and Spreadsheets and Zoho Writer. Of the two, I like the interface and features in Zoho Writer writer more, but Google Docs and Spreadsheets probably has more utility because of its connection to Google accounts.

Have any of you tried these programs or others? If so, share your thoughts about them by adding a comment to this post.