I use the NewsRob app for offline aggregation of my Google Reader feed, but its always bothered me that it requires me to enter my Google username & password through the app itself. There are several other RSS apps that do the same. There's no way I'm going to enter information that important into an app that someone else wrote, so I created a separate Google account just for Google Reader.
I could be wrong, but shouldn't apps be able to use Google's OpenID or OAuth or have access to the currently logged in Google account on the phone to access Google Reader?