This kind of makes me sad, and I'll tell you why. My first thought when reading the news was to come up with an idea to use this exploit for good. This is only "good" if you like wasting free time, which it has the potential to do.
Announcing, from PanTechnoCo, Always Always New: the link sharing service that only shows you new links.
Keep in mind, this isn't a product, but a toy. I just wanted to play around with the idea. You can post links and you can follow links. The site will show you all links you haven't visited yet, even if you visited them without following links from itself. If you had enough people to keep populating this thing, and you just kept reading, you could be in trouble.