Did you notice that the Google Reader now offers offline mode? It can download and save your files so that you can read them even when you are not connected to the internet. It is powered by Google Gears. I tried to create an application by going thru the steps in the Developer Guide Tutorial. It was not that easy to follow it. It could have be a bit more simpler. If you are looking for a simpler version, its available here.
BTW, there is a new Eclipse plugin for Google Gears is already in the drawing board. Not publicly available and sent only thru invitations. If you are interested in trying out, please send a mail to prakash at cypal dot in.