As mentioned in the constructing a news search engine tutorial, Yahoo Pipes! is a free, web-based tool that provides several options for manipulating and filtering your information stream from blogs, favorite news web sites, and more. To get started quickly, clone an existing pipe and tweak it for your needs.

Here are two examples of pipes designed to output news from research-based news services that contains certain key words. Note: there is a brief delay after the page loads while the pipe runs to produce its output.
Environmental news
Health news about the brain, learning, or teens

Pipes can also be useful to create a unified feed of the new online content you generate personally - through your blog, Flickr account, delicious account, and similar tools - so that friends and family can keep up with you. Although this is not a research-based application of Yahoo! Pipes, it may provide a way for you to experiment with this useful tool.

To get a visual sense of how to put a pipe together, view this silent video on YouTube that shows how to combine three feeds to produce a unified output stream, and then how to pull that output into Feedburner (you could substitute your own favorite RSS/feed reader in place of Feedburner at this step).