Innovative use of Yahoo! Pipes and Grazr. Give it a try.
"As far as I know OnePipe is the first solution to offer generic, on-the-fly feed filtering based on URL parameterization."
OnePipe is a browser bookmarklet I created to filter any feed by topic. It's simple to use: install the bookmarklet, navigate to any website whose feed you'd like to filter and click the OnePipe button. You'll be prompted to enter any topic or word after which OnePipe will generate a custom feed that only contains those items that match your keywords. The exciting part about OnePipe is that it can be used over and over again.