Gmail, Calendar and Docs without an internet connection

Offline access to Gmail, Calendar and Docs has recently been made available to Google Apps domains

Gmail: Gmail Offline is a Chrome Web Store app based on the Gmail web app for tablets.
Calendar: When offline, you can view events and RSVP to appointments.
Docs: You can view documents and spreadsheets offline.

Editions included:

Google Apps, Google Apps for Business, Government and Education

How to access what’s new:

Gmail: Install the Gmail offline app from the Chrome Web store. Administrators need to first allow access to the ‘Chrome Web Store’ service.

Calendar and Docs: Click the gear icon at the top right corner of the web app and select the option for offline access.