Google Docs will slowly roll out an option to view and edit documents offline using Google Gears. Unlike the Google Reader implementation, Google Gears will automatically detect when you're offline and will take care of constantly downloading the changes so that your documents are available locally.
When you are offline, you can access your documents by simply going to docs.google.com or by clicking on a desktop shortcut. The documents can be edited offline and Google will try to solve the conflicts if your collaborators edited the documents while you were offline. "In the case where your edits conflict with another collaborator's, you will see [a message]. If you'd like to keep your changes, you have the option of copying them into the document. Also, you can click Show differences to compare different revisions and revert to the one you want," explains Google.
Google Docs blog lists some potential use cases. "It's all pretty seamless: I don't have to remember to save my documents locally before packing my laptop for a trip. I don't have to remember to save my changes as soon as I get back online. And I don't have to switch applications based on network connectivity. With the extra peace of mind, I can more fully rely on this tool for my important documents."
Hopefully you're luckier than me and you see an "Offline" like at the top of Google Docs' homepage. If you get access to the offline Google Docs, share screenshots and opinions in the comments. Don't forget that when you are offline, your documents are available by simply visiting docs.google.com and without entering your Google password. For now, spreadsheets and presentations aren't accessible offline.
Update: Google Docs offline guide.