I've had it with RSS feeds that spontaneously reload the entire backlog. It's surprising how common this is, and I'm unsure why it happens as it's never happened on my blog. One that just did this seems to have re-dated all articles to today's date, which isn't really ideal.
The trigger for me was the (several) Google blogs I subscribe to all doing it multiple times this week. Most annoying!
So if this happens with a blog, I'm gonna ruthlessly unsubscribe. I suspect this might have a positive impact on my productivity too.