Today, uberblog Engadget posted a story regarding Apple delaying the iPhone and Leopard, which turned out to be a false alarm. However, during the period that Engadget claimed the delays as fact, Apple's stock plummeted - well not plummeted, but it was definitely affected by the news - as CNet reports. I just find it extremely interesting that a "mere" blog can have such a powerful effect on the real world.
Update: My roommate Chris blogged about this as well.