We are depended on many Google Services like Gmail for emails, Blogger for blogs and Google Reader for feeds for our day to day task. We can't even think about losing our Google or Gmail account. For this reason it is necessary to have offline backup of Gmail, Blogger or Google Reader account.
Unfortunately Google doesn't offer any such backup service. Here is Gookup excellent java based tool which lets you to take offline backup of Google Services. You can backup Gmail, Google Reader & Blogger blogs. Gookup is command line utility.