One of the great parts about web apps is that they are on the web, and can be accessed from anywhere you have net access. One of the worst parts about web apps is that they are on the web, and if you don't have access to the net you don't have access to the apps. Google has long been talking about being able to move web apps onto the desktop and let them work offline, and now is putting that talk into action. Today they launched Google Gears, a browser plugin that enables web apps to run even when no connection is present.
Interestingly, they also have released the source code for the plugin, perhaps to encourage adoption for multiple platforms and to get more interest in Google Developer Day. Obviously support will be limited at first, but the ultimate goal is to allow people to use any online apps offline until a connection can be restored, which would be particularly useful to people with unstable or slow connections, or to prevent work from getting cut off in the event of an outage.