All feeds via Newsisfree.com have changed URL location and are therefore not working at the moment.
Here's the announcement about this change:
Three feeds I know about that are affected:
reuters_oddly -- new feed url: http://xml.newsisfree.com/feeds/97/4997.xml
iht_opinion -- new feed url: http://xml.newsisfree.com/feeds/18/1218.xml
theonionfeed -- new feed url: http://xml.newsisfree.com/feeds/47/2447.xml
I'm sure there are others.
I also noticed that saloncom started showing a parse error today. The feed URL attached to that account is valid, however.