I am looking for a web based rss/rdf/atom aggregator, but since I could not find anything matching my requirements small and must export xml files, I decided to write my own.

On CPAN I found XML::Feed, which does exactly what I want namely repepresent feeds as perl hashes:

This module attempts to remove those differences by providing a wrapper around the formats and the classes implementing those formats (XML::RSS and XML::Atom::Feed).

For example, dates are handled differently in each of the above formats. To provide a unified API for date handling, XML::Feed converts all date formats transparently into DateTime objects, which it then returns to the caller.

The module has a list of dependencies, but with the help of dh-make-perl it is pretty easy to create debian packages directly from cpan modules.