Google Docs with Offline Support Spotted in the Wild

One thing that's been 'coming soon' for almost a year now is offline support for Google Docs and other Google services via HTML5. Lately, Google has said that it is putting the final touches and that the feature is already in testing internally. Offline support for Docs, Gmail, Calendar is coming this summer, Google has promised, and the first signs are already showing up.
A Google Docs user managed to get a version of the service with the offline-support interface enabled. The feature itself was not working, but this is the first glimpse of what the UI will look like.

When Google Docs will not be able to connect to the Google servers, indicating a lost connection, it will automatically switch to offline mode.

The users will be notified via a black bar on top of the page, if this testing interface ends up the one being used, which will enable them to switch from offline to online mode and back.

Users will probably be able to go into offline mode even if they have an active internet connection, to save on data traffic usage for example.

When offline mode is enabled, all new documents, spreadsheets and so on, or changes to existing ones will be saved locally and will be synced once connectivity is regained or when the user switches back to online mode.

Copies of some stored documents, probably the most recent and the most frequently accessed will be kept locally, enabling users to search edit them even if they don't have an internet connection.

All of this relies on a mix of HTML5 technologies, like local storage, IndexDB and so on, most of which are new technologies which have not been thoroughly tested.

This is the reason why it took so long for the Google team to build offline support, it had to work on perfecting the technologies which make it possible along with working on the feature itself.