Google gears makes web applications work offline. It seamlessly synchronizes and stores an image of the online version on your local pc for offline use. Quite a lot of web apps are available on google gears. Some common ones that I have used - Google Reader, Autodesk draw, Zoho Writer etc. It first came out for windows in mid 2007 and now they have a fully functional, stable version for Linux. Installing it and using it is really easy. Let's see how.