There are many free RSS aggregators out there for you to use for both Windows and Macintosh computers. There are even online aggregators that you can access via your web browser. Personally, we use RSS Bandit.
It requires the Microsoft .NET Framework to be installed (which you can get from Windows Update). For a listing of other RSS aggregators, do a Google search or view this listing at Wikipedia.
To learn more about RSS, again Wikipedia is a great resource.
Feel free to comment on this new feature on this RSS message board post.