Several new features for Google Apps have come on stream over the past weeks.
Using Google Gears it is now possible to have your most recent mail and attachments available off-line. The amount depends upon your volume of mail - mine stores around 6 months on my laptop.
Additionally, there is labelling of mail which can then be displayed on panes within the displayed inbox. This allows you to categorise your mail and see it in these categories. Using label:unread and label:starred means that two panes (off to the left, right or under) will list these in full view when in your inbox.
The Google calendar is now also available off-line. Though this is available on mobile phones, having your calendar and appointments permanently accessible takes away the fear of losing this information at vital times.
Working off-line goes against the "in the clouds" concept but these features allow one to access mail and attachments when there is a connection problem.
Although in Beta, these mean some really good functionality using GApps.
The latest Google Apps additions have given us the confidence to go totally "Google Apps for Education" in our school. We are doing away with our webmail service and going Google over this weekend (staff first, then students later) - will let you know how this goes.