I've noticed a trend where a lot of feeds are including large blocky ads at the bottom of each feed item. I can live with that; a little ugly, but I can skip them easily.
Today I saw something new:
That's right: two complete posts consisting of nothing more than the same ad.
Scrolling down shows me that the very next item is exactly the same add from "The Fail Blog", another site operated by the same company.
Ads with content I can stand. Ads without content? *unsubscribe*