Tony Ruscoe is at it again, he found an experimental server for Google Docs and noticed a link at the top that says "Experimental! Offline Access" in big red letters. Clicking the link popped up a Google Gears box that asks the for access.
Once the user has given Google authority to sync documents, it begins working. After it is done, you are able to launch http://docs.google.com even without internet access. Unfortunately, as Tony points out, you can't really do much more than rename document files (not even presentations or spreadsheets yet). Given the uselessness of this feature, it's not hard to imagine it's still in the early stages and could take a while for it to be officially implemented.
The "experimental server" is still a mystery to me, so I can't verify this information first hand -- however Tony is very trustworthy, and anything he says can generally be taken at face value.
[images via Google Blogoscoped]