the Jabber stuff is pretty neat, but you've written a very rude RSS aggregator.

you appear to be fetching the entire feed every single time without taking advantage of things like Etags and If-Modified-Since headers.

you could improve things significantly by making use of LWP's mirror() instead of get(). that will handle conditional requests for you automatically.

it's also a good idea to make sure you support all the HTTP return codes properly.

and fetching feeds every 5 minutes is way too frequent. some sites, like slashdot, will ban your reader if it hits them more often than once per hour.