Credit:
Offline access to Google Docs is coming, as announced today by Phillip Tucker over at the Google Docs blog. Personally, I'd be a lot more excited if I didn't just upgrade to Firefox 3, since this is a Google Gears based project (and Gears isn't yet compatible with that version of Firefox - see my Twitter log for documentation of my Firefox problems).
On the upside, though, Gears will ultimately come to FF3 through some form or fashion, and Firefox 2 users can start enjoying offline access themselves very soon - some even today. The migration of accounts with access to offline capabilities begins now.