Google announced a new API this week, the Google AJAX Feed API. In a nutshell, it allows you to use Google's cache of RSS feeds (the same cache that makes Google Reader work) for whatever purpose you want: recent posts from your favorite blog (à la Feed2JS), mashups, or anything else.

Results are returned in JSON, XML (the original feed source), or both. It supports all flavors of RSS and Atom.

I've just started playing with this -- but here's a completely unstyled list of headlines from CNN pulled down and displayed using this API: RSS4Lib Google API Test.