As before [1, 2] I will mention feeds that I unsubscribe from not because I find them boring but because they annoyed me to the point of unsubscribing.
Lockergnome is usually a pretty good resource for lots of things, in particular I read their RSS & Atom Tips in my aggregator but I am now unsubscribing from this useful resource due to spam.
(edited to remove the name of the company advertising)
I can understand the need for advertising in RSS feeds and will tolerate it in full text feeds, I will however not tolerate it in feeds that only show you a snippet of the story forcing you to open their page and view their banner ads. They are already seeing revenue from me when I click on their RSS item – when it is interesting enough – so why should I also see the ads in my RSS reader. If they want to see ad revenue from me, then they should feel an incentive to get me to open the full article in my browser by posting interesting content. As it stands, they just annoy me.