Windows: If you're looking for a way to manage your Google Docs without the need to sign in via your web browser, gExplore can help you out. It allows you to upload and download files in your Google Docs account directly from Windows, and even send PDFs to your Amazon Kindle.
In addition to standard uploading and download, you can also encrypt files before sending them over to Google Docs, edit collections, share files and collections with other users, add notes to files, run permission audits to see full sharing details on each of your files, email files, and send PDF copies to your Amazon Kindle. Although the web interface for Google Docs is pretty robust, it can be a lot faster to upload and download files with gExplore. If you're looking to save some time, or just prefer a desktop interface, it's a free download that's worth a look.